What die fish in an aquarium


Why do fish in aquarium suddenly start dying?

Unfortunately, like other living creatures, fish can die ahead of time. Why it happens? The answer to this question is often sought by novice aquarists. It is much more effective to prevent the appearance of such a problem than to look for the causes of a pet's death.

Ideal if you asked this question before the moment the tragedy occurred. Warned, so ready to control all the nuances of the aquarium and try to avoid the early death of aquarium inhabitants. Consider the most common reasons.

Nitrogen poisoning

Nitrogen poisoning is the most common problem. It often concerns beginners who have no experience in dealing with aquarium animals. The fact is that they are trying to feed their pets to the dump, forgetting that with this increases the amount of waste. By the simplest calculations, each fish per day leaves feces equal to 1/3 of its weight. However, not everyone knows that in the process of oxidation and decomposition nitrogen compounds appear, consisting of:

  • Ammonium;
  • Nitrate;
  • Nitrite.

All these substances are united by their toxicity. The most dangerous of them is ammonium, the excess of which will be the main cause of death for all inhabitants of the reservoir. This happens most often in newly launched aquariums. The first week after the start becomes critical. There are two options for increasing the amount of these substances in aqua:

  • Increase in the number of inhabitants;
  • Breakage of the filter;
  • Excessive feed.

It is possible to determine the surplus by the state of water, more precisely by smell and color. If you noted the darkening of the water and the smell of rot, then the process of increasing ammonium in the water is started. It happens that when visually inspected, the water is crystal clear in the house for fish, but the smell makes you wonder. To confirm your suspicions, ask special chemical tests at pet stores. With their help, you can easily measure the level of ammonium. True, it is worth noting the high cost of tests, but for a novice aquarist they are very necessary if you do not want to lose all your pets for a couple of days. If time corrects the situation, then the death will be avoided.

How to lower the level of ammonia:

  • Daily water change ¼
  • Water should stand at least a day;
  • Check the filter and filter element for serviceability.

Wrong launch of fish

Imagine what a fish is experiencing when it goes from one water to another, the parameters of which are significantly different. Buying a fish in a pet store, you deprive it of its usual environment, transferring it to your own, which is completely unfamiliar to the fish. Water differs in hardness, temperature, acidity, etc. Of course, the reaction to such a change will be stress. A sharp change in acidity of at least 1 unit indicates death for sensitive fish. Sometimes the difference in acidity is much more, so the shock that the fish is experiencing can end in death.

Proper adaptation of the fish to the new environment:

  • Pour the water with the fish in a large vessel;
  • Top up some water from the common aquarium;
  • After 10-15 minutes, repeat the procedure;
  • Dilute with water to at least 70% solution.

Even if several new fish managed to survive after a crushing change of water parameters, then they will surely die in the first illness. Immunity is significantly undermined, which means that bacteria attack them first. Carefully follow the aeration, cleanliness and new inhabitants. At best, the health of the fish is normalized.

Fish diseases

No one wants to blame himself, so beginner breeders blame the disease. Unscrupulous sellers only reinforce their doubts, because they have a goal to sell expensive medicine and cash in on. However, do not rush for a panacea, carefully examine all possible causes of death.

Blame the disease is possible only if the symptoms have been noted for a long time. The fish died away gradually, and not just died in an instant, for no apparent reason. Most often, the disease is brought to the aquarium with new residents or plants. Death may occur due to malfunction of the heating element in cold weather.

Going to pet stores, you should be aware of what exactly you need medicine. Each of the drugs directed to a specific disease. Universal drugs do not exist! If possible, consult an experienced aquarist or ask a question on the forum, knowledgeable people will tell you what to do in this situation.

Of course, the disease can not kill a healthy fish. Why die fish in an aquarium? If the death occurred, then the immunity has already been undermined. Most likely, the first two errors occurred. Do not rush to launch new residents, no matter how beautiful they are.

What to do to protect the aquarium:

  • Organize quarantine for new inhabitants;
  • Sanitize fish or plants.

What to do if the disease started up in the aquarium:

  • Change one tenth of the water daily;
  • Increase the temperature;
  • Strengthen aeration;
  • Remove the carriers of the disease and those who are clearly infected.

Remember which fish you ran at home last. Individuals brought from other countries can be carriers of rare diseases, and it is sometimes impossible to detect and classify on their own.

Water quality

Utilities do not set themselves the task of purifying water to such an extent that aquarium residents feel comfortable. Their goal is to make it safe for the person and his home. Hence the popularity of bottled water. Tap water contains the maximum chlorine level. In large cities, there may be a probability of changing water from artesian to desalinated. As a result, water hardness will increase, leading to mass death. You can notice this by the modified behavior of the fish - they begin to rush around the aquarium in a state of horror.

You can avoid this situation. For this:

  • It is not recommended to change at a time more than 1/3 of water
  • Settle the water in an open vessel for at least a day;
  • If possible, purchase a water filter with three secretions;
  • Use chemicals.

Please note that deaths are those fish that were already in a state of stress.

O2 deficiency

This option is the rarest of all. Oxygenation of a fish house is always adequately assessed even by beginners. The first thing they do is buy a compressor. With him, not terrible choking fish.

The only possible option is to increase the temperature and, as a result, lower oxygen in the water. This can happen at night, when the plants are rearranged from the production of oxygen, to its absorption. To avoid this, do not turn off the compressor at night.

Aggressive neighbors

Before you go to the store for pets, think over to the smallest detail, can there be several species in one fish house? You should not rely on the competence of the seller, since the main goal for him is to realize as much of the goods as possible.

A few fundamental rules:

  • Big fish always tend to eat small ones (even in the case of herbivorous species);
  • Many succumb to intraspecific aggression;
  • Some are able to stick to small neighbors, which ultimately leads to death;
  • The strong always eat the weak;
  • Buy only those fish whose peace-loving nature you are sure of.

Unfortunately, it is impossible to establish why fish die. The death of a pet can happen even to experienced breeders. Be attentive to the fish, and you will definitely notice a change in behavior and in time eliminate the cause of anxiety. More often, fish die in an aquarium because of an oversight, and not according to other criteria.

What to do if you find a dead fish?

Suddenly discovered that you have died in a fish tank and do not know what to do now? We have compiled five tips for you to cope with the death of the fish and what to do if this happened. But, remember that even in the most ideal conditions, they still die. Often, suddenly, for no apparent reason and very annoying for the owner. Especially if it is a large and beautiful fish, such as cichlids.

Attention! First of all, check how your fish breathe!

Often aquarium fish die due to the fact that the water parameters have changed. The most pernicious effect on them is the low level of oxygen content in the water. Characteristic behavior is that most fish stand in the surface of the water and swallow air from it. If the situation is not corrected, then after a while they begin to die. At the same time, such situations can occur even among experienced aquarists! The oxygen content in water depends on the temperature of the water (the higher it is, the less oxygen is dissolved), the chemical composition of the water, the bacterial film on the surface of the water, the outbreak of algae or ciliates. You can help partial water changes by turning on aeration or directing the flow from the filter close to the surface of the water. The fact is that during gas exchange, it is the fluctuations of the water surface that play the decisive role.

1. Look at

Check and recalculate your fish daily, while feeding. Are they all alive? Are everyone healthy? Does everyone have a good appetite? Six neons and three speckled, everything is in place?
If someone is missed, check the corners of the aquarium and lift the lid, maybe it is somewhere upstairs in the plants? But you can not find a fish, it is quite possible that she died. In this case, stop searching. As a rule, a dead fish becomes visible anyway, it either floats to the surface, or lies on the bottom, the floor is snagged, stoned, or even falls into the filter. Every day, inspect the aquarium, did the dead fish appear? If found, then ...

2. Remove the dead fish

Any dead fish, as well as large snails (such as ampoules or mariz) should be removed from the aquarium. They rot very quickly in warm water and create soil for the development of bacteria, the water is muddier and begins to stink. This all poisons other fish and leads to their death.

3. Look at the dead fish

If the fish is not too decomposed, do not hesitate to examine it. This is unpleasant, but necessary. Are her fins and scales full? Maybe her neighbors beat her to death? Are the eyes in place and are they dull? Strongly swollen belly like in the picture? Maybe she has an internal infection or she has poisoned herself with something.

4. Check water

Every time you find a dead fish in your tank, you need to check the quality of the water with the help of tests. Very often the cause of fish death is the increase in the content of harmful substances in the water - ammonia and nitrates. To test them, get in advance tests for water, better drip.

5. Analyze

The test results will show two results, either everything is fine in your tank and you should look for the cause in another one, or the water is already rather polluted and you need to replace it. But, remember that it is better to change no more than 20-25% of the volume of the aquarium, so as not to change the maintenance conditions of the fish too dramatically.
If the water is all right, then you need to try to determine the cause of death of the fish. Of the most common: disease, hunger, overfeeding (especially dry food and bloodworms), long stress due to improper housing conditions, age, the attack of other fish. And a very frequent reason - and who knows why ... Believe me, any aquarist, even the one who has been keeping a complex fish for many years, has sudden deaths to watch his favorite fish.
If the incident is a single case, then do not worry - just watch out for new fish or die. If this happens all the time, then obviously something is wrong. Be sure to contact an experienced aquarist, it's easy to find now, since there are forums and the Internet.

Fish die in the aquarium: reasons

Why die fish in an aquarium?

Sometimes in the aquarium, the fish begin to die one by one. Their owner makes a rash decision - he goes to the pet store and buys any funds offered by the seller. But nothing helps. So, why fish die in an aquarium? There are several reasons for this.

Bacteria - fight!

The main problem of all troubles in an aquarium is dirty water. Beginning breeders, as a rule, forget that the fish not only breathes and eats, but also feces. As a result, the increased content of nitrate, ammonium and nitrite leads to a mora. And the first two are especially dangerous. Poisoning with these substances can be seen with the naked eye: there is a smell of rot, the water becomes cloudy and the question: "Why do the fish die in the aquarium?" can be considered closed.

Bacteria that fight poison and toxins live in the filter media and in the soil. It is important to clean both substrates carefully but carefully. Otherwise, you can destroy the fighters for health. Thus, there is no need to clean the aquarium to sterility and periodically turn off the filter (otherwise anaerobic microorganisms will settle there). By following these simple rules, you can maintain the health of this biosystem and then the fish will not die.
To restore the lost balance, the following instruction is recommended:

  1. Stop feeding for a short period of time. Fish without food can last for several days
  2. Measure the level of toxic substances using special tests (sold at the pet store)
  3. If the readings are equal to 2 ppm, then it is necessary to replace half the water in the aquarium, but gradually, otherwise the death of the fish will not stop.
  4. Follow the second and third points for several days until the microflora is restored.
  5. In no case can not use antibiotics. They are completely destroyed biobalance!

It is important to remember that the aquarium, as a fabulous teremok, can fall apart if it is overpopulated. Fish die because of gluttony. If overfeeding occurs, food debris will simply begin to decompose. Therefore, it is better to reduce portions than to increase.


As a rule, the temperature, pH and hardness of the water in the pet store is very different from the aquarium breeder. The strongest stress, and therefore the reason why the fish die in the aquarium, can become an ordinary room in a new habitat. Changes in pH can even kill pets or lead to their fatal illness. How to help them endure stress?
First you need to put the bag with the newly purchased fish in the aquarium and attach it with a clothespin to the glass. Then - weak aeration. After 10 minutes you need to pour into the package aquarium water. Repeat this step every 12-15 minutes. After half an hour, you can release the fish in a new home. And finally, the last step - the addition of anti-stress drugs and feeding.

Living water or dead?

If the fish die after the change of water and, moreover on a massive scale, it means that the water supply companies are to blame. They are usually interested in the health of a person, not his pets. Companies may suddenly change the Ph or the hardness of the water. In addition, it is strongly influenced by the melting of snow.
In this case, it is recommended (especially in spring) to defend water, at least a day. In addition, it is desirable to heat it to 70 degrees, and then gradually cool. Another tip: do not make large changes of liquid (more than 30% of the volume). It is also important to avoid sudden changes in temperature in the aquarium.


Very often, this is the reason newcomers hear from sellers to the question: "Why do I have fish die in an aquarium?", Because the latter are interested in profits from sales of expensive drugs. It is important after the purchase of pets to quarantine, and sometimes - preventive treatment. But even in this case, the fish can get sick. In this case, to prevent the pestilence, the ill person should be placed in a separate aquarium.
Imported fish sometimes bring rare species of disease that cannot be determined without special laboratory analysis. In pet stores there are a lot of drugs that can save pets from misfortune, but it’s better not to be consulted about the choice of treatment from the sellers, but from experienced aquarists. But, as a rule, before treating the problem itself, it is necessary to look for its source: reduced immunity and, consequently, the poor state of the composition of the water.
Fish die from many causes, but the pillars of care for them are unchanged: regular cleaning of the soil and water filtration, timely replacement of water, not overfeeding.

Why die fish in an aquarium, what to do?

Why do fish die
or the story of the sad fate of Goldfish!

The motive for writing this article was the communication on the form with a certain citizen who wrote in the section on helping to determine the disease of fish.

"Help, please, I have a telescope at the age of 6 months. I haven’t eaten anything for three days. It floats on the surface with difficulty, there is enough air. There is no external damage and no swelling. Help if you can still, it’s a pity to lose fish."

Being a conscientious and sensitive person, I gave her a plan of action and events according to the full scheme, advised the preparations. And then, when I wrote everything, I thought - why should I treat it so radically, maybe the reason for the poor health of the fish lies on the surface? :)

In this connection, I asked a citizen: "Tell me, what is your aquarium volume, who lives there besides the telescope, etc."

When I received the answer, I just went nuts! I’m trying to get along with treatment and help, but it turns out that ... read the answer: "Aquarium 80 liters. 1 gourami, 2 thorns, 2 gold, 2 telescopes (1 patient, another healthy, but for some reason does not grow), 2 danios, 2 small antsistrus, 2 speckled catfish, 1 angelfish, 2 ampoules ... ".

The reason that the telescope was bad - was revealed !!!

Imagine if 16 people planted in an eight-meter hut, how much would they stretch? ... Whatever the conditions in this hut, the sea would start a month later.

Vendors of pet shops are selling fish to beginner aquarists, using their insatiable desired “I want this fish, this one and that one and those catfish”. At the same time, neither of them think about the further fate of the fish.

Sad! But for some reason, this is exactly the fate of "cramming nevpihuemoe" comprehends only aquarium inhabitants. Imagine, mother and daughter come to the pet store and say: "Give us 15 cats, 3 Yorkshire terriers, 5 chinchillas and one sheep dog and 2 more parrots do not forget." Unfortunately, with aquarium fish this is exactly what happens.

And then, after a while, a convulsive scripture begins and the search for an answer to the questions: why the fish die and die, why do the fish lie at the bottom, float or swim on the surface, do not grow and do not eat!

HERE'S OWN, WHAT HAS BEEN AWARDED ME WRITE THIS ARTICLE!This is some kind of attempt to stop the mockery of fish! An article for future similar questions. An article that will somehow help newcomers and people who are going to buy an aquarium to understand that the fish are the same living things as we do - they grow, require certain conditions of detention, have their own characteristics, etc.

Very clearly, this problem is visible in Goldfish (pearls, comets, telescopes, veils, shubunkin, oranda, ranch, koi carps, etc.). People either do not know or do not understand that this family of fish belongs to large species. In fact, they need to be kept in ponds (as it was in Dr. China) or in large aquariums.

But it was not there! People for some reason have developed a Hollywood stereotype that Goldfish looks beautiful in a round small aquarium.

HOWEVER, THIS IS NOT THE CASE!!! The minimum volume of an aquarium for a pair of goldfish should be from 100 liters. This is the minimum in which they can live normally, and it’s not a fact that they will grow "to their full height."

Therefore, recalling the above example with a citizen, which has an 80-liter aquarium, in which: 4th scrofula, scalar, gourami and others ... it is not surprising to hear "My golden fish does not eat anything, lies at the bottom or swims belly to the top." And it touches the question, why do they not grow?))) But how can you grow here, you wouldn’t die!

In addition, in this example, there is a relative compatibility of fish. We must not forget that Scalaria is a peaceful, but still South American cichlid, and somehow it’s not a friend with goldfish. The same goes for the gourami - they are peaceful, but snooty individuals come across.

Summarizing what has been said, I earnestly ask everyone not to violate the norms and conditions of keeping fish.
Do not be greedy!
And then your fish will grow beautiful and big.

Somewhere I read that for 1 cm. The body of a fish without a tail should have 2-3 liters of water in an aquarium. Who cares here is a link to the compilation - How much can the fish in an aquarium X liters (at the end of the article, select the aquarium of the desired volume).

Now I would like to talk about other reasons that lead to poor health of fish, without any visible reason (signs of the disease are not visually visible).

If the norms of the volume of the aquarium are not violated, the compatibility of the fish and their number are not violated, and the fish still float or vice versa lie at the bottom and swallow air, then the reason may be:

Poisoning fish with nitrogen, ammonia,
and more simply poop

We live in the air, and the fish in the water. Parameters of aquarium water directly affect the health of the fish.

In the process of life, aquarium fish and other inhabitants defecate, another organic matter dies, the remains of food decompose, which leads to excessive saturation of water with nitrogenous compounds that are detrimental to all living things.

Thus, the cause of poor health or a pestilence in fish may be:

- lack of care for the aquarium (cleaning, cleaning, siphon, no filter or replacement of aquarium water).

- overfeeding fish (the presence in the aquarium is not eaten feed).

- untimely disposal of dead fish, etc. (some novices watch snails burst dead fish, this is absolutely impossible).

What to do in this case? It is necessary to eliminate the sources of nitrogen excretion:

- urgently transplant fish into another aquarium with clean water;

- strengthen aeration and filtration;

- to clean the aquarium, and then replace it? aquarium water to fresh;

- fill in the filter aquarium coal;

It should always be remembered that Aquarium water needs to be replaced weekly. However, this is not always good - old water is better than fresh, especially for young aquariums, in which the biobalance is not yet tuned. So this should also be done with the mind and as needed. If you see that the water in your "young aquarium" is not green, not muddy, etc. Replace at the beginning of 1 / 5-1 / 10 of the volume of aquarium water. However, one should always keep in mind that clear water is not an indicator of its purity. With that said, it is necessary to develop your own “tactics” of water changes based on the volume of the aquarium, its age and fish preferences, etc.

Emergency fish transplant - This is a temporary measure, if the fish is very profitable. As a rule, when a fish is not feeling well (lying on the bottom, swallowing air, swimming on its side, etc.), such an action brings it to life and after 2-3 hours it is cheerful and cheerful.

It should be remembered that such a transplant should be done in the water at about the same temperature as in the aquarium, the water should be separated (preferably), do not forget to provide aeration. And yet, if there is no other aquarium, an emergency temporary transfer can be carried out in a basin or other vessel.

About coal. Aquarium coal is sold in any pet store. It is not very expensive, so I recommend to buy it in reserve. Coal - this is a great additional measure in the fight against "shit and other evil spirits." If it is not at hand, you can temporarily take human activated carbon, wrap it in gauze or bandage and put it in the filter.

There are also so-called ion-exchange resins, for example, zeolite, they also refer to absorbents as coal, but they work, if you can say so at a more subtle level — removing nitrites and nitrates from the aquarium — decomposition products of ammonia, which in turn is formed from dead organics and waste products of hydrobionts.

Water filtration. It's simple. The aquarium filter must be suitable for the volume of aquarium water. Additional helpers: aquarium plants, as well as snails, shrimps and crustaceans.

In the end, we can advise the drug for quick cleaning of the aquarium from sewage - TetraAqua Biocoryn.

Another reason that the fish die can be the wrong adaptation of newly purchased fish.

Well, firstly, you should not release new fish immediately into the aquarium. Everyone knows that. Let them acclimatize: Therefore, see the article All about Purchasing Transplant Fish Shipping!

Secondly, the fish that lived in the pet store or grew up in another pond got used to certain water parameters (pH, hD, temperature) and if you transplant them into water with radically opposite parameters, this can lead to their death in a day or a week.

Actually therefore for the correct adaptation there are so-called quarantine aquariums. You kill two birds with one stone: check whether new fish are contagious and adapt them to new conditions. The quarantine principle is simple - it is a small aquarium (another reservoir) into which new aquarium inhabitants are launched and within a week they are checked for lice, as well as they gradually add aquarium water from the aquarium in which they will live.

You can do without quarantine, but it is a risk! As a rule, it carries in 80% of cases, but 20% still remain. To neutralize these 20% I recommend to transfer fish with the drug company Tetra AquaSave (Tetra AquaSafe), read here DRUGS AND TETRA AIR CONDITIONERS. This preparation "improves" aquarium water and reduces the stress of fish during transplantation.

The third reason that the fish is bad is asphyxia, caused by the lack of sufficient aeration of aquarium water.

The obvious signs of asphyxiation (suffocation) in fish are: frequent opening of the mouth, heavy breathing, wide opening of the mouth - as if yawning, the fish swims near the surface and there is enough oxygen.

You should know that the fish breathe oxygen dissolved in aquarium water, which they pass through the gills with water and if it is not enough of the fish simply suffocate.

Enhanced aeration and bringing it back to normal will correct the situation!

Another - the fourth reason for the ascent of the fish with a belly to the top can be the use of tap water

Opinions on this are different. While talking and discussing this topic, some comrades say: "Yes, all this is fikhgnya, I fill in the unstable tap water in the aquarium and everything is fine - the fish will not die." However, it is worth noting that tap water in many regions of the CIS is simply terrible! It contains so much bleach and other impurities that it is scary to use it. Somewhere, of course, the water is better here and “carries” - the fish do not die. In the Czech Republic, for example, tap water is generally spring water from the Karlovy Vary sources, but alas, where is the Czech Republic, and where are we ?!

Therefore it is very important to use only separated water for the aquarium. In addition to the fact that chlorine will evaporate from the water and heavy impurities will settle, excess oxygen will also be released, which are no less destructive for fish.

What to do if you poured tap water and fish from this poplohelo? Ideally transplanted into separated water. However, if you originally poured water, then you probably do not have separated water. One way out is to add aquarium chemistry that stabilizes the aquarium water. For example, the aforementioned Tetra AquaSafe or TetraAqua CrystalWater.

The fifth reason for the death of fish - a violation of the temperature

The generally accepted temperature measure of aquarium water for many fish is 25 degrees Celsius. But too cold water or too warm leads to all the same symptoms: the ascent of the fish, lying on the bottom, etc.

With cold water, everything is clear - you need to buy a thermostat and bring the reduced temperature to the desired one. But with too warm water is much more complicated. Usually aquarists encounter this problem in the summer, when the water in the aquarium boils and rolls over 30 degrees, from which the fish become lethargic and "faint."

There are three ways out of this situation:

- cool the aquarium water handicraft: using frozen 2n. bottles from the fridge. But - this is not very convenient, because frozen water quickly gives off cold and you need to constantly change the bottle. In addition, jumps and temperature fluctuations - there, no less harmful than just elevated water temperature.

- sold special installation cooling aquarium, but alas, they are expensive.

- buy an air conditioner and install it in a room with an aquarium, in addition to room stuffiness, the air conditioner will knock down the aquarium heat. The last option in my opinion the most acceptable.

The sixth and seventh reason

Sometimes the cause of bloating the fish and swimming a belly or side to the top is overfeeding. Again, this reason is largely related to goldfish, because they suffer from gluttony, overeating and begging. Do not enter them on occasion. Feed them exactly as much as it should be. Otherwise, your gluttons will earn inflammation of the gastrointestinal tract or, more simply, they will suffer from constipation!

Another reason for which the fish can lie down for no apparent reason is stress. Well, do not like her neighbors and that's it. Or it often happens that they take young fish, and all the boys and one female grow out of it, and as a result, the boys start a showdown - who is in charge. The weak begin to chase and tyrannize, with the result that they are hammered into a corner, lie on the bottom, well, and die. There is only one way out, to resettle everyone, give them to friends or back to the pet shop.

What else can affect the health of fish:

- Excessive lighting or stress from it;

- decorating the aquarium with chemically dangerous decorations (metal, rubber, plastic);

- overdose of drugs;

Summing up, it is possible to make an unequivocal conclusion that the correct maintenance of fish is a panacea for many aquarium ills. If you are attentive to your aquarium dwellers, they will thank you too.
beauty and longevity!

We also recommend that you read the brochure Navigator 3: an interview with an ichthyopathologist. Below is a link to the pdf-version, which you can download, as well as its test version.

To read and / or download the Navigator

click on the picture below

If you do not have a PDF reader installed, we recommend that you use AdobeReader by downloading it from the official site.

Useful video about the treatment of fish, which will help solve the question of what to do with a dying fish?

Video section of the site on the treatment of aqua fish

What to do if a guppy dies?

Unfortunately, sooner or later aquarium fish die. The most common cause is the wear and tear of the body, as a result - its old age. Life expectancy depends on many factors, but it has been proven that large fish live longer than small ones. As for guppies, they belong to small fish, which can grow 5-7 cm in length in an aquarium. Live relatively short: 3-5 years. Why are these fish dying in the aquarium?

Causes of Poecilia reticulata death: water pollution

Guppies (Poecilia reticulata, Guppy) suddenly die one after another? Then you need to do something to prevent the death of other fish. Sometimes razvodchiki go to specialty stores, buy funds or drugs, but nothing helps. If the cause is not found, it will be difficult to eliminate the effect. The main reason for the death of many fish in the home aquarium is poor housing conditions, namely, dirty, inadequate water. Poecilia reticulata is no exception.

Recommended parameters for guppy content: temperature 22-26 ° C, pH 7.0-8.5 pH, hardness 10-18 °. With sharp changes in environmental conditions, the fish will start to hurt. Also, in the absence of weekly replacements of 20% of water with fresh and clean water, guppies will actually breathe their own waste. The lack of high-quality filtration and aeration will also negatively affect fish life.

Watch the video with guppy content recommendations.

Increased concentrations of ammonia, nitrates and nitrites lead to exhaustion of the fish. They can become poisoned with harmful substances suddenly, if the aquarist does not notice the smell of rot, turbidity of water. What should be done in this case? It is important to purify water from impurities with the help of special harmless substances that are sold in stores, or a filter. Completely replace the water should not, but only part of it.

Another reason why the young guppies in the aquarium do not die in time is the unprepared water. Do not run fish into a tank with chlorine-rich water. She should insist 4 days before pouring into the container. You can use dechlorinator, which is sold in some pet stores.

Pay attention to the state of the filter - on the sponge breeding good bacteria that fight against toxic substances and microbes. The main thing is to timely clean the filter filler and replace it if necessary. Disruption of biological balance can lead to a sharp deterioration in the health of fish.

Over-feeding guppies can also cause them to die. Not eaten feed splits, forming ammonium vapors. If you put the fish on a fasting day, at least once a week, and remove leftover food, you can fix the problem. On the day of harvesting, make measurements of the level of nitrates and ammonium, the pH and hardness of water, the level of CO2 and oxygen. If the level of toxic substances is 2 ppm or more, you need to replace 50% of the water, but not immediately, but within a few days. Over time, the microflora will recover. You can not use antibiotics to combat ammonia, otherwise you can destroy all the good bacteria.

Although guppies are considered hardy fish, but under the wrong conditions of the aquatic environment, they can get sick. Diseases are another reason why these fish die in the aquarium. The infection enters the water with poor-quality food, sick fish and infected plants, and then rapidly multiplies in dirty water. A terrible infectious disease of guppy is tuberculosis, or mycobacteriosis. Unfortunately, it is not treated: the fish must be destroyed, and the entire aquarium is strictly disinfected.

The parasitic ciliate Trichodina Modesta can cause the disease trichodynia. Treatment of fish is possible with the help of methylene blue, trypaflavin, attorney salt and other medical preparations. Most often, fry and young fish die from the disease.

Long-tailed guppies with veiled fins can get the so-called "red scab". This deformation is visible on the reddish coating on the tail, later its rays will flake off. In case of delayed treatment, the tail will be "eaten." In this case, you need to do a mechanical trimming of the damaged part of the fin, and add chloramphenicol or salt to the water.

Acclimatization and improper compatibility as a result of the death of fish

If newly purchased fish suddenly die in an aquarium, they probably could not adapt to the conditions of their new environment. Water temperature, acidity and hardness of the new aquarium should be similar to those in which they lived before the purchase. Before you run the fish in a common tank, put them in a two-week quarantine. The difference in pH and dH by one unit can kill the fish. What should be done in order for guppies to transfer new conditions?

Place the portable bag with the purchased fish in a new water, pin it to the glass with a pin. You can run a weak aeration aquarium. After 10-20 minutes you can add a little aquarium water to the bag. It is recommended to repeat the procedure every 15 minutes. After 1.5 hours, you can release the fish in the otsadnik. You can add anti-stress drugs and some feed to the water.

See how to properly transplant fish in the aquarium.

Sharp temperature changes in the aquarium should be avoided. Do not make too frequent water changes, and no more than 30% of the total volume of the tank. Siphon the soil in a timely manner, remove and process boiled water contaminated scenery.

What else are killed aquarium guppies? Perhaps a few novice aqurahumists guess about such a problem as the wrong settlement. And, most surprisingly, other Guppy can be the cause of death. Unsuccessful settlement implies a close environment, incompatibility of characters, disproportion of the number of males and females in the aquarium. If all the males are killed in the kennel, it means that there are too many females on them, or there was a fight between the males in tight territory.

Choose a spacious 50-liter tank for one fish to settle the guppy. On one male settle 1-3 females. Install reliable shelters, plant plants that would prevent conflict situations. Also settle Poecilia reticulate with small, peaceful fishes. Related viviparous fish are their best neighbors (swordtails, mollies and petilia). Do not settle the fish with aggressive, fast and predatory fish. It happens that guppies die of stress and physical exhaustion.

Noticed that the fish jump out of the aquarium, and die right on the floor? Most likely, there is not enough aeration in the water, the fish have experienced a jitter, or the water quality is inadequate. To avoid such a problem, check the behavior of all the inhabitants of the nursery, make measurements of the state of the water.

Is it necessary to change the water if one of the fish died :: how to change the water in the aquarium :: Aquarium fish

Tip 1: Do I need to change the water if one of the fish died

Often, inexperienced aquarium owners rush to replace all the water in a tank if one fish dies, as they fear the contamination of the aquarium. So is it really necessary to completely change the aquarium water, or are there other rules for dealing with an aquarium in which one of its inhabitants died?

The question "opened a pet shop. Business is not going. What to do?" - 2 answers

Change or not change

If only one fish dies in the aquarium and the water looks clean, it is not necessary to change it, because after changing the water, it will be necessary to wait for the restoration of the ecosystem and biological balance. Therefore, it is enough just to add fresh water, renewing the old one. If the fish has died from an infectious disease or has lain in the aquarium for several days, the water should be replaced, while washing out the aquarium.
When adding fresh water to the aquarium, at least one third of the old water should remain - at the same time, fresh water should have similar hardness and temperature indicators.
If you still need to clean the aquarium, you need to remove all live fish and plants from it, wash, disinfect and dry. After that, new water is poured into the tank. In the first few days a short-term bacterial outbreak with water clouding can be observed in the aquarium - no need to worry, it will pass by itself. After that, as the water becomes transparent again, plants can be returned to the aquarium, and it is advisable to launch the fish in about a week. Replacing water is often the most effective way to get rid of bacteria, but for fish it is a lot of stress, so you should not abuse it.

How to change the water

An electric or vacuum pump is great for changing the water in an aquarium. A siphon will also do well with this task, with the help of which the walls and bottom of the aquarium are easily cleaned of food and residue residue. To prevent the water from turning green, the aquarium should be placed away from sunlight and turned off artificial light at night. In addition, it is necessary to periodically remove excess plants from it and feed the fish less so that the water is not contaminated by the remnants of food.
Somiki-antsitrus, which slide along the aquarium walls and eat plaque on them, will also help to clear the water.
Partial change of water in the aquarium should be done every week, changing it to 1/5 of fresh water. In order for the water to always be clear and transparent, you should launch mollusks and daphnids into the aquarium. Many owners of aquariums are trying to clean glass containers with snails, but they are not very effective in doing this and besides they are spoiling quite a lot. Water problems are usually characteristic of "young" aquariums - later their own ecosystem arises in them, the situation normalizes independently. The main thing - to follow the rules for the care of the aquarium.

Tip 2: How to change the water in a small aquarium

Mini-aquariums - an attractive interior decoration. But unlike large tanks, equipped with all necessary equipment, there are some problems with care. If you follow the basic rules, including the replacement of water, you can avoid the flowering of the aquarium and create fairly tolerable conditions for the fish.

You will need

  • - soft distilled water;
  • - net capacity;
  • - bucket;
  • - scraper.


1. It is believed that a small aquarium is easier to clean than a large one. However, this is the first misconception of inexperienced aquarists. It requires more frequent replacement of water, because the products of decomposition of fish waste are accumulated here most of all. In addition, intensive plant growth can cause a lot of trouble.

2. The water in a small aquarium should not be completely changed. It is enough to replace up to 1/5 of the total volume. This should be done quite often - once every 3-4 days.

3. Replacement water should only be soft, room temperature, so you should have a constant supply. Only tap water from clean dishes that should be used only for this purpose. To defend the liquid must be at least three days.

4. Replacing water in a small aquarium is not difficult. Calculate the required quantity for replacement. For example, in an aquarium with a capacity of 10 liters, it is necessary to change 2 liters (1/5 of the total volume).

5. Scoop out the required amount of water with a special scoop with a long handle. Scrub the walls of the aquarium and add fresh soft water. Then collect water in a clean dish and leave it to stand until the next procedure.

6. The water in the mini-tanks evaporates very quickly. Check its level regularly and top up if necessary.

7. Fully change the water in the aquarium should be as rare as possible, because it violates the biological equilibrium. However, this must be done once a year to transplant plants and clean the walls of the aquarium and filter.

8. To replace the water completely, remove the fish and place them in a jar for a while. Drain fluid with a hose. Remove excess algae. Clean the rocks and walls of the aquarium.

9. Then pour the settled water. Add bacteria and let the aquarium stand for a couple of days, then run the fish into it.


For dwelling in a small space, choose guppies, gourami and tetra. These fish feel pretty good in mini-aquariums. Also in the pond you can settle a cockerel, neons look beautiful. If the fish have grown to a rather large size, they need to be deposited in a larger tank.

Very impressive look and feel good in a small aquarium, not only fish, but also other marine and freshwater inhabitants, such as shrimp.

Help is needed! In our aquarium -100 l die fish. Why?

Natalia A.

Well, who on the 2nd day after the bay of the aquarium launches fish ??? The aquarium itself starts up for 2 weeks with the equipment turned on, BUT WITHOUT FISH !!!! This is your fatal mistake, so the whole fish was laid. The biological equilibrium in the aquarium should be established first and the turbidity of the water at the start must be, the bacterial outbreak passes and the water clears itself. And then exclude colored soil, if it is dyed and seashells, they raise the water hardness. And before you start a fish, learn pliz literature for beginners.

larisa martirosova

Elena, there can be several reasons: plants, scenery, water, stones.
If the water in the well is good, then ... further analyze in turn. If there is no experience with a small aquarium, they might miss something. Maybe some fish can not stand any plants. Atlas on aquarium fish there? And then came the deadly poison from a dead fish.
In general, we need a specialist. Very sorry. Perhaps there is a society that deals with aquarium fish. Look for it. site.
How to console you? May you have great luck in something else so that it balances your grief!

Elnikov Denis

The first turbidity, then the clarification of water is the installation of biologicheskogo equilibrium. After clarification and it was necessary to run the fish. And so I recommend to take a book for a beginner aquarist - see if you have missed during the preparation

Yuk @

survived the most unpretentious fish ...
For the future: do not collect as many types of fish - the cocks do not get along with the fish in just fluffy fins, roosters gnaw them quickly and small fish, such as neons, can easily eat. Angelfish with danios are not worth it, danios are moving schooling fish (at least 6 pieces, only then they show themselves in all their glory, neons are also flocks) who love to drive an angel and goldfish. if there are no thick algae bushes, then they should not coexist. Barbs with neons ... good appetite barbs - adieu neon fins. Pekylii, Mynesia - a classic of the genre, with which it was necessary to begin
Regarding feeding, it is not necessary to feed dry food - the water quickly disappears and not all fish love this food. Advice, buy a frozen CORRETRU, MOTYL, DAFNIA, ARTHEMIA, WOLFIA (herbal supplement), RABBE. Here is the food that ALL fish will eat with pleasure, and it will not rot. At least, in order to understand how much fish you need to eat, throw small pieces until they greedily grab, as soon as they start turning their noses, start looking; if you don’t pick up food from the bottom, it means enough. Wait ten minutes and the hose removes the rest of the food from the bottom.
Regarding water. If the aquas is near the window or the place from which direct sunlight can fall on it - remove it from there, the water will bloom, you will be tormented to change. If there is aqua lighting, how powerful are the lamps? On my 120 liter there were 2 lamps of 15 watts and this was enough with my head.
Concerning diseases. I strongly recommend finding such preparations for fish as MITELENA BLUE, MALACHITE GREEN, COPPER SULFATE, ACRYMET and other products in the zoomag, and there are others, but these are the most common from many diseases.
About algae. Rinsing under running water is not enough to wash off all the microbes, soak the plants in a solution of methylene blue for at least a day.
regarding water from the well - do not bother - in reality, these fish live and not in such conditions.
If anything, contact us think of something.

Li Ka

A lot of things you did wrong ...
On the second day after the launch of the aqua run fish => the first obvious mistake!
4 neons, 4 barbs, 2 catfish, 2 cockerel, 4 angelfish, 2 gold, 4 danios, 4 picies, 2 malinesia => second mistake! I advise you to read the appropriate literature with whom and with whom you can hold, the appropriate temperature regime for each separately, etc., etc.
And then the fish lived in the hostel of an international university ... sorry ...
If everything were in order with water, so the barbies with cockerels would have battered peaceful fish.
But what exactly was with water - only fish can know this. And here is the third mistake.
For water, in fact, it is necessary to follow! And not so, poured, the poor fish launched. Moreover, even if the smell of the water was bad. Fish poisoned you with hydrogen sulfide (presumably)
Hydrogen sulfide poisoning And the fourth, at least a mistake. The fact that you have planted the surviving fish in simply defended water. For them, this is not the best option ...
But what do you do next => learn the theory first. Books, the Internet ... And then try to practice.
I don’t have tips on how to save the remaining fish ... As an option, give aquarists or acquaintances who have aquas in working order, ask for water (from the aquarium, of course, and not from the tap) And run the remaining fish into this water. At least in a 3- or 5-liter jar. And watch the water!
Good luck and no offense :)

Nastya Polyakova

A terrible mistake of landing fish of angelfish are predators that feed on gold neon will bite off the tails of an improper landing. Most likely the barbs are slaughtering all other fish with scalars. You need to read a lot of literature before you plant fish in such unrest.

Irish @

YOU did not run the aquarium correctly. It takes at least a week for everything to stand with the equipment turned on. For an accelerated start-up, water is taken from an established aquarium, added to a new one and left to stand. The fish you bought are not compatible with each other. Denis correctly wrote about turbidity = this is a normal process, but at the beginning. Bought a grotto, and they are from synthetics, was the smell? If there was, then you need to soak it well. And you can not just shove everything in the aquarium ... What is possible, boil ... or wash thoroughly with soda. Perhaps restarting the aquarium will help. There are drugs that accelerate this process, special bacteria. And before you sit some fish to the other, make sure that they are compatible. Scrofula are considered as assholes, but if you decide to start them, then ONLY them ... and cleaning (soil siphon and topping up with fresh water) should be done often so that the water is clear. And for another gold one, you need 50 liters of water so that it shows all its natural beauty and can feel comfortable. GOOD LUCK !!!

Andrey Kovalenko

yes ... so much criticism of the author of the question (horror :)), dear Elena Kudryavtseva, reading your question, I noticed one important detail: "they poured it (the ground) - first small, THEN BETTER - multi-colored, ... and it smells unpleasant - please write what fraction of soil (which is bigger), perhaps the reason is that the food gets between large stones, it is natural for the somas not to get it, you have no meats, it turns out that the remains of food rot (this is where the unpleasant smell came from), the water spoils and the fish are dying. By the population you have already suggested. If I still turned out to be right about the water, then you don’t need to run on a new one, remove large stones, siphon the soil, do not run the fish yet, change 40% of the water, as the water stops smelling (and if it rots the food remains, it smells rotten eggs) you can run 3 fish (preferably of course catfish). Well, like so far everything.

Igor Vasiliev

Well, pounced on you, "specials." Itself, probably, and not that got up with fishes and an aquarium. Dont be upset. You have experience first, bitter, but yours. You have told you about your mistakes, but no one has said that the water in the well, from the well, and the ground water in general, is “dead” water, that is, there is no life in it, the most important thing is bacteria. Do not worry much and start your aquarium again, the main thing is do not rush.

Die guppies in the aquarium! Why?

Irina Shnidrova

It is necessary that the water was settled. They bought fish where the seashells disappeared, they began to clean the shells, and they saw the horror there was a fish with a belly full of holes (it turned out there were predators). Due to the fact that the water was hot, some fish jumped out of the aquarium.

Prince of Wales

nothing can boil ...
1. Remove all the shells, they make the water hard.
2. Do not do a spring-cleaning in the aquarium once a month. Better every week little by little.
The key to success in aquarism is the ability to grow plants. If you can not maintain a biobalance sufficient for plants, then you can not contain fish.
In fact, everything is simple. It is necessary to stop thinking in terms of sterility. There is no sterility in nature. Totally. And every time you step on the same rake.


Let's start with the fact that 8 liters is not the volume for a normal aquarium. More precisely, the volume, but for an experienced aquarist. In small volumes it is very difficult to maintain the biobalance. The literature advises beginners to begin (sorry for the tautology) with 100 liters. I start with 60, which also turned out to be not bad. Indeed, the more a bank, the less problems with it, the better everything works in it (if you have the necessary equipment). Here they have already said that it is not necessary to arrange a gene-cleaning every time. In one of the options, the water should be drained once a week, a third or a quarter with simultaneous siphon of the soil. In a small aquas, this will also be a problem - thrust a siphon, here, in fact, a third has merged, if not more. The fish must be properly transplanted, and not immediately tossed into new water. Information on the forums of the sea, just do not be lazy to read. Here you have good sites -,

Elizabeth Halliwell

8l - not an aquarium, but a can of water. Balance can not be achieved and maintained in such a volume.
For beginners from 30-50l
8 l for a maximum of 2 male guppies.
Nothing to blame for the disease - die from poor care

Why did a golden fish die?

Zhenya Gerasimova

You are joking?? ? Half a year is too much for her !! ! And it was necessary to clean it immediately from the aquarium. Now probably decomposed and infected all the fish !!!! What did you think then when she was dying ???? A comet is the simplest and most unpretentious species of small-sized goldfish with a long, ribbon-like (often forked) tail that exceeds body length. The longer the tail fins, the higher the estimated instance.
Comets with a swollen body, like a voiletail, are considered to be a marriage (according to some experts, this is a different breed). The developed dorsal fin and slightly elongated other fins give the fish a great harmony.
The color of the comet may vary, but those individuals whose body color is different from the color of the fins are of particular value. In China, silver fish with a bright red or lemon yellow tail were considered to be particularly beautiful, 3-4 times longer than their body length.
Despite the fact that comets grow well and mature in almost any environment, it is difficult to work with them. These strong, restless fish often jump out of aquariums.Females give relatively little calf. Together with goldfish are suitable for keeping in the garden pond.

Vladimir Kostyuk

Overfed, the air still needs to be served. Eat a lot - breathe hard. It rummages and dirt does. The filter is necessary with foam rubber and a pump (a small motor inside). This fish eats as much as it is and is always small, little pig.

Julia Andreeva

ONE goldfish need an aquarium of 50 liters, a pair of 100 liters. This is without any guppies there.
It is not good to feed gold, but qualitatively and little by little, once a day. If you feed "good" - it means a lot, then gold is also dead from gluttony.