How to change the water in the aquarium


How and how much to change the water in the aquarium, the frequency of water changes

How to change the water in the aquarium?

In this article we will discuss a fairly simple, but at the same time, a difficult question regarding the change of water in the aquarium. It is simple because there is no need to replace water in the aquarium. However, there are a lot of nuances and certain specifics that you need to know on this issue. The matter is further complicated by the lack of complete, comprehensive information on the Internet. As a rule, information about the change of water in an aquarium is either compressed, or one-sided, or only a certain part is covered.

No exception was our site. Here, for example, article Boiled, melted or distilled water for aquarium. It seems the article is good, but narrow and concise.

So let's fix this defect. As much as possible and fully consider the question: "How to change the water in the aquarium?" That in turn, will give us the opportunity to make the change of water as simple and effective as possible.

For convenience, let's break down the article into the following sections:








Many novice aquarists are faced with different opinions about the need to change the aquarium water. Often in the forums or from friends you can hear the phrase: "That I do not change the water at all and .... everything is OK" or "I rarely, rarely ... and also OK." Here that, at the beginner and there is a stupor! How so? I’ve furnished the whole balcony with buckets, how I carry a water carrier from the bathroom to the aquarium, but it turns out that this is “monkey work” !? Without tormenting for a long time, I will answer you - do not listen to these "uncles and aunts"! They mislead you. AQUARIUM WATER MUST BE CHANGED!

And the thing is this! In the process of vital activity of all aquatic aquatic organisms (inhabitants), the aquarium itself, or rather, the water becomes clogged. For example, an excess of food, fish feces, dead leaves of plants and other organic matter. All this "dirt" turns into the most terrible poison - ammonia, which is destructive for all living things in an aquarium. Further, the nitrifying bacteria that are in the water, the filter and the soil "decompose" ammonia to nitrite (poison), then nitrate ("weak" poison), and then the remains are converted to gaseous state and leave the water.

So, no matter how many useful nitrifying bacteria are in the aquarium of colonies, no matter how many live plants are in the aquarium, which also partially absorb ammonia, no matter how powerful the filters are ... no matter, the above poisons tend to accumulate. And you can bring them ONLY REGULAR REPLACEMENT OF WATER TO CLEAN.

What happens in an aquarium for those who do not change the water for a long time? Many aquarium fish tend to adapt and live in the worst conditions - get used to the poisons. However, this function of "survival in any conditions" is not eternal. In fish, irreversible changes occur in the internal organs, mucous membranes and gills. Fish weaken, their immunity falls. And the “Doomsday” comes when an outbreak of a bacterial, fungal or infusorian attack occurs ... not many survive!

In total, the change of aquarium water is one of the most important ways to maintain "health in the aquarium", one cannot do without it. Laziness in this matter is a fatal mistake!



There is such a non-contagious sore in fish, called Gas embolism. In a nutshell - this is the entry of small air bubbles into the blood vessels and blood of fish. As a result, there is a blockage of blood vessels. Fishes begin to swim sideways, the behavior becomes alarming, fearful. The fins and the whole body begin to tremble convulsively. The movement of the gill covers slows down, and then completely stops ... further death!

A frequent cause of gas emboli is inadequate settled water for an aquarium. The fact is that tap water (tap water) is excessively saturated with air bubbles that are so small that they are not even visible to the human eye. Just imagine how much water “poured through the pipes” until it reached your tap!

Thus, filling the tap water in an aquarium with fish - YOU ARE VERY RISK. Yes, in practice, everything can do, but this is a game of Russian roulette.

What happens to water, if it is defended? What happens is that small bubbles gradually merge and come out of the water. Water saturation by air decreases, the risks are reduced to zero.

In addition, it is worth noting that in the process of settling water for the aquarium, heavy and harmful compounds, for example, chlorine as sediment at the bottom of the container and film on the surface of the water, settle.


Everything is simple and should not cause much difficulty. The water in the aquarium should settle in a container with a wide neck: a bucket, a basin, an enamel saucepan. You understand that in a bottle with a narrow neck, excess air goes out poorly. Container for sludge should not be metallic, rusty or made of toxic substances or paints. Plastic buckets, perhaps the best and easiest option for defending aquarium water.

About time! ... The longer the water settles, the better! I personally defend the water for 7 days - this is convenient and coincides with my Sunday schedule for changing the water in the aquarium. In general, such terms of water settling 1-14 days roam the Internet.


But this is really a problematic issue for owners of large aquariums and not large apartments! How to defend 50, and then 100 liters of water?

If this is a new aquarium and the first launch of the aquarium is made, you can immediately fill in the aquarium with tap water, defend it and at the same time add air conditioners to improve the quality of water.

If water is needed for replacement, then our first glance is the only rational option is to purchase construction containers (plastic buckets for mixing mixtures) for 50, 100 liters.

Other ways to prepare aquarium water in the first place include: boiling, freezing water, as well as its purchase of water in the store. See more about this. HERE.

Also, aquarium water can be prepared using special air conditioners such as: Tetra AquaSafe, AMMO-LOC, Sera aqutan and others.

Here is a video about one of them:


Almost in all books, on all sites, they write standardly what needs to be changed weekly? part of the water from the total volume of the aquarium. This is a generally accepted norm, BUT NOT DOGMA. Here, look, please statistics of the survey, which is conducted on our site.

How often do you change the aquarium water to fresh?

As you can see, everyone changes the water in different ways and the weekly replacement of aquarium water is not a dogma! Why? It's very simple - everyone has different aquariums, different fish, plants, and so on. For example, there are fish that love the "old" water and the frequent change of water only annoys them (the family of labyrinth fish). The abundance of living plants, also reduces pollution in the aquarium. In the end, someone has a large aquarium, someone has a small, someone has a big fish, and someone has a small one.

All this individual specificity of the content of fish excludes the concept dogma number and frequency of substitution of aquarium water. And there is only one advice - you should adapt yourself and you should come to the conclusion about how often and how much water you need to change in your aquarium. In this case, you must take into account the volume of the reservoir, the population of the aquarium, the individual characteristics of the fish, the presence or number of plants, the filter power, the presence of ion exchange resins in the filter, and so on.


Finally, I want to give attention to the beginner aquarists, that it is only necessary to change the aquarium water after cleaning the aquarium, and not before.

That is, first we:
- clean the filter and other equipment;
- wipe the walls of the aquarium;
- we thin and cut the plants;
- siphon soil;
- produce other manipulations and permutations;
- and only then we replace part of the water with fresh one;

If you have any questions, any comments on the article, please leave them in the comments - we will discuss.

Useful video about changing aquarium water

Learning to do the replacement of water in the aquarium

An aquarium decorates every home, but is also often the pride of the inhabitants of the room. It is known that the aquarium has a positive effect on the mood and psychological state of a person. So, if you look at the fish swimming in it, there comes peace, calm and all the problems are relegated to the background. But here we should not forget that the aquarium requires and care. But how to care for the aquarium? How to clean the aquarium and replace the water in it so that neither the fish nor the vegetation will suffer? How many times do I need to change the fluid in it? Probably worth talking about this in more detail.

Tools for replacing aquarium water

Novice aquarists suggest that replacing water in an aquarium is accompanied by some kind of disorder spilled by water around the house and a huge waste of time. In fact, all this is not so. Changing the water in an aquarium is a simple process that does not take you long. In order to perform this simple procedure, you just need to have the knowledge and, of course, to acquire all the necessary tools that will be your permanent assistants. So let's start with what a person should know when starting the water replacement procedure. First of all, this is what all aquariums are divided into large and small. Those aquariums that do not exceed two hundred liters in their capacity are considered small, and those that exceed two hundred liters in volume are the second type. Let's start with the replacement of aquarium water in small objects.

  • ordinary bucket
  • crane, preferably ball
  • siphon, but always with a pear
  • hose, the size of which is 1-1.5 meters

The first replacement fluid in the aquarium

In order to perform the water change for the first time, you need to connect the siphon to the hose. This procedure is necessary to clean the soil in the aquarium. If there is no siphon, use the bottle, after cutting the bottom of it. With a pear or mouth, draw water until the entire hose is filled. Then open the tap and pour water into the bucket. This procedure can be repeated as many times as you need to replace. By the time such a procedure takes no more than fifteen minutes, but if a bucket without a spout, it will be a little more. When you do this for the first time, the skill will not be there yet, respectively, the time period may also increase. But this is only at the beginning, and then the whole procedure will take a little time. Aquarists know that changing the water in a large aquarium is easier than in a small one. Just need a longer hose so that it reaches the bathroom and then the bucket is no longer needed. By the way, for a large aquarium, you can use the nozzle, which easily connects to the faucet and fresh water will easily flow. If the water has managed to settle, then, accordingly, you will need a pump that helps to pump fluid into the aquarium.

Water change intervals

Beginner aquarists have questions about how often it is worth changing the water. But it is known that the complete replacement of fluid in an aquarium is extremely undesirable, as it can lead to various diseases and even to the death of fish. But it must be remembered that in an aquarium there should be such a biological aquatic environment that would be not only acceptable fish, but also had a positive effect on their reproduction. It is worth remembering a few rules that allow you to comply with all the necessary conditions for the normal existence of fish.

Water replacement rules:

  • The first two months should not replace the fluid at all
  • Subsequently, only 20 percent of water is replaced.
  • Partially change the fluid once a month
  • In an aquarium that is over a year old, the liquid must be changed at least once every two weeks.
  • Full replacement of the fluid is made only in emergency cases.

Compliance with these rules will preserve the necessary environment for the fish and will not allow them to die. It is impossible to break these rules, otherwise your fish will be doomed. But it is necessary not only to change the water, but also to clean the walls of the aquarium and at the same time not forget about the soil and algae.

How to prepare water for replacement

The main task of an aquarist is to properly prepare the water for replacement. Taking tap water is dangerous as it is chlorinated. To do this, use the following substances: chlorine and chloramine. If you familiarize yourself with the properties of these substances, you can find out that chlorine disappears quickly when it is settled. For this it is enough for him only twenty-four hours. But for chloramine one day is not enough. It takes at least seven days to remove this substance from the water. There are, of course, special preparations that help fight these substances. For example, aeration, which is very powerful in its effects. You can also use special reagents. This is, above all, dechlorinators.

Actions when using a dechlorinator:

  • dissolve dechlorinator in water
  • wait about three hours, until all the excess is evaporated.

By the way, these same dechlorinators can be purchased at any pet store. Sodium thiosulfate can also be used to remove bleach from water. It can be purchased at the pharmacy.

Replacing water and fish

Changing the aquarium water is easy, but you should not forget about the inhabitants. Fish every time there is a change of water, are under stress. Therefore, every week it is better to perform the procedures to which they gradually become accustomed and already perceive them calmly over time. This applies to any type of aquarium, regardless of size: small or large. If you keep a constant eye on the aquarium, you often do not have to change the water. Do not forget to take care of the general condition of the fish dwelling. So, it is worth changing the algae that grow in the aquarium, because they pollute the walls. It takes care of other plants that need not only to be changed as needed, but also to cut the leaves. To add additional water, but how much it can be added, is decided in each case separately. Do not forget about the gravel, which is also cleaned or changed. You can use a filter for water purification, but often this does not affect the conditions of the aquarium. But the main thing is not only to change the water, but to ensure that the lid in the aquarium is always closed. Then the water is not so quickly polluted and it will not have to be changed frequently.

Video on how to replace the water and clean the aquarium:

How to change the water in a small aquarium :: how to care for fish in a small aquarium :: Aquarium fish

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.

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

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, you need 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. Чтобы заменить воду полностью, выньте рыбок и поместите их в банку на время. Слейте жидкость при помощи шланга. Удалите лишние водоросли. Почистите камни и стенки аквариума.

9. Затем налейте отстоянную воду. Добавьте бактерии и дайте аквариуму постоять пару дней, после чего запустите в него рыбок.

Обратите внимание

Для обитания в маленьком пространстве выбирайте гуппи, гурами и тетры. Эти рыбки довольно хорошо себя чувствуют в миниаквариумах. 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.

Helpful advice

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

How to change the water in the aquarium :: how to decorate the aquarium at home :: Care and education

How to change the water in the aquarium

The mistake of many novice aquarists is the frequent change of water. But the water in the aquarium often, and especially in full, can not be changed. Water changes completely only in exceptional cases. This occurs when fish are killed or if parasitic microorganisms have appeared. With a stable mode, the water in the aquarium does not change for years. Partially change the water when cleaning the walls of the aquarium and the bottom. If the water began to smell - it must be changed.

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You will need

  • - bucket;
  • - glass scraper;
  • - a transparent hose with a nozzle-siphon.


1. In order to change the water, take a bucket, glass scraper, transparent hose with a nozzle-siphon. Hose is better to use PVC, as rubber emits unwanted components into the water. There is a hose with a rubber bulb with a built-in valve that lets one-way water through. There are electric siphons that run on batteries. But a simple hose is the cheapest and most convenient. If you are going to shorten the plants, take the scissors. You can just tear them off with your hands.

2. Place the bucket below the water level in the aquarium. Dip one end of the hose into the tank, and the other end into the mouth and gently suck in, then quickly lower the hose into the bucket. The main thing - do not sip water. It can be done differently. Dip the hose in the tank completely, clamp the ends and transfer one into the bucket and release. The other end is brought to the piles of dirt in the aquarium. The hose is difficult to direct to the right places, so put your hand in the water and drive them where there is not enough food or dirt has accumulated.

3. Do not take the hose too long. The diameter of the hose is best to take 10 - 15 mm. If you take a large hose, the water will pour out too quickly. With a large current of water, sand can rise from the bottom, even curious fish can be tightened. You can put a funnel on the hose, it will help to simplify the cleaning procedure and slightly weakens the flow. When cleaning the bottom, about 1/5 or 1/3 of the water flows out.

4. After cleaning the bottom completely, you do not need to change the water in the aquarium. Just add fresh water, which should have the same characteristics as in the aquarium. If there are tropical fish in the aquarium, the temperature of the topped-up water should be the same as in the aquarium or 1 - 2 degrees higher. If cold-water fish live in the aquarium, you should not heat the water. Pour water in small portions, gradually.

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Full replacement of water in the aquarium

Complete replacement of water in an aquarium is extremely undesirable, so it should be carried out only according to a special need - for example, if the aquarium needs to be repaired or sanitized.

In order to drain all the water, prepare a bailout, where you need to catch all the fish - it will become a temporary aquarium for them. If there is no spare aquarium, you can use a bucket or basin. In case there are a lot of small fish, make them the right aeration.

If possible, all plants are also removed from the aquarium. If the reason for the complete replacement lies in plant diseases, then they need to be disposed of, and after changing the water, plant others.

Once you have removed all the fish and plants, you can begin to drain the aquarium. Take a bucket or basin, which will pour water, bring it to the aquarium. To complete the replacement of water in the aquarium, first drain all the old water with a hose into a basin or bucket.

As soon as the aquarium is empty, it must be washed, sanitized and dried, and then filled with new water. Remember that after that the ecosystem should be normalized and the balance should be adjusted, therefore in the first 2-3 days a bacterial outbreak will occur, which will pass by itself. The water will grow cloudy, but as soon as it becomes transparent again, you can plant the plants, and it is better to start the fish in 7-9 days.

Remember that to abuse the full replacement of water is not worth it. If, for example, one fish died, this is not a reason for panic; if several of them are sick, then they need to be transplanted and tried to cure; and only if there is an outbreak of any infection, and drugs do not help, then you need to change the ecological environment, that is, water.

Replacing the water in an aquarium is sometimes considered the most effective tool in the fight against bacteria, because they do not react to drugs due to their protective mechanism. But still, before changing the water, think more than once - this is a huge stress for fish.

To change the water in the aquarium, instead of a hose, you can use a vacuum or electric pump. The simplest device is a siphon, which consists of a narrow tube and a cylinder. With its help you can clean the bottom and walls of the aquarium from the plaque and food debris.

Electric pumps have recently become quite popular, but they are used to pump water from small containers, and in other cases it is better to use a regular siphon.

❶ How to change the water of the fish :: how to change fluids :: Aquarium fish

How to change the water from the fish

An inept attempt to clean the aquarium can result in the death of all fish and plants in it. Many novice aquarists mistakenly believe that frequent water changes help maintain normal biological balance for fish. But the water evaporates, and dirt and mucus can appear in the aquarium ...

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

You will need

  • - settled tap water


1. To maintain a steady regime of "fresh" aquarium, do not change, but pour water. The volume of tap water should not exceed 1/5 of the volume of the aquarium. Otherwise, the hydrochemical composition of the “old” water changes dramatically, and then your pets can get sick or float up the belly.

2. Remember, the main thing is not the content. fish, and habitat control. Even a small substitution of water (1/5 of the volume) brings "stress" for the inhabitants of the aquarium, but after a couple of days the biological balance is restored. If you change half of the water, then the balance returns to normal in about a week, but some fish and plants will inevitably die. According to the site, completely change water possible in exceptional cases: due to soil contamination, darkening, the appearance of mucus or harmful microorganisms. Otherwise, with the correct perennial balance, the fish themselves, plants and microorganisms serve as a biological filter.

3. The aquatic environment in the aquarium is formed during the first two months, therefore, during this period add water can not. When a young habitat has formed, add water no more than 1-2 times a month, periodically cleaning the glass and collecting debris from the ground with a hose. For aquariums with a volume of 20 liters pour defended plumbing water, preferably slightly warm (up to 40 or 50 degrees). After a year, clean the entire soil so that the optimum medium does not age.

Related videos

Helpful advice

If you first decided to get fish, then experts recommend starting not with a traditional aquarium of 20-30 liters, but with a small reservoir of 100 or 200 liters. It will be much more difficult to destroy its biological balance, each time adding water, and you will learn the proper maintenance of the fragile world of exotic underwater inhabitants.

How to change the water in the aquarium for turtles :: how to change the fish air in the aquarium :: Equipment and accessories

How to change the water in the aquarium for turtles

Turtles are often kept in the apartment as pets. For the maintenance of aquatic turtles, an aquaterrarium made of glass, plexiglass or plastic is necessary. So that the pet does not hurt, the water in it must be periodically changed.

You will need

  • - bucket or other container;
  • - baking soda;
  • - brush.


1. The water in the aquarium with a bug should be changed 1-2 times a week. If the tank is equipped with a filter, this can be done less frequently, since the water will stay clean longer. Without a filter and a change of water, the liquid quickly becomes polluted and blooms; in such conditions, the animal will be sick more often.

2. Remove the turtle from the aquarium and place it in a cup, a deep plate or a bucket at the time of the water change, from which it cannot escape. Take care not to drop the pet, and keep in mind that it may scratch or bite you, trying to break free. Leave the bucket in a safe place.

3. Drain the water from the aquarium and remove all accessories. Clean it from the inside without using chemicals. You can only rub the terrarium with ordinary baking soda, but after that you need to thoroughly wash the powder off the walls. Fill the container several times and pour it out.

4. Wash stones, snags and everything that was in the aquaterrarium. Soil when keeping aquatic turtles is not required. Disassemble the filter and rinse it. Reassemble and fasten tightly in place.

5. Place the accessories back in the aquarium and pour warm filtered water into it. If you put a turtle in cold water, it can get sick. The optimum water temperature is 20-26 ° C.

6. Examine the bug itself, brush the shell with a brush (you can use a toothbrush). Return the pet to the aquarium. You can immediately start to swim it, but you can put it on the islet and wait until it crawls into the clean, warm water.

Helpful advice

Drying in an aquarium with a turtle should occupy at least a quarter of the total area. It is desirable to make an approach to it sloping so that the animal could easily climb to the shore, relax and warm up.

How to change the water in the aquarium ???


I see how many people - so many opinions. In my opinion you are the first time, filling the aquarium, brought some infection. Therefore, put the fish in a jar with separated water (at least 24 hours). Just see that they do not suffocate there. If there are many fish, it is better to take a few cans. Fish in banks may suffer from lack of oxygen, but they cannot go blind there. It is a myth. Then pour the aquarium, otdraivayte it with hot water and soap, rinse thoroughly with hot water without soap. Then fill it with cold water, or let cold water let it stand. At the bottom of the poured coarse washed sand and pebbles, plant algae, run the snails. And only then run the fish. And in the future, all the water in the aquarium does not need to be changed, only once every two weeks collect the accumulated dirt from the bottom of the tank and add the required amount of separated water instead of evaporated and removed along with the dirt. In aquarium, after some time, a biological balance must be established and it will work as a closed biosystem. True, this applies to aquariums of 80 liters or more.


1. 3 days before the start, infuse tap water (for bleaching powder to evaporate)
2. you need to catch fish with a net or net and place it in a jar.
3. Then take out the water, rinse them and put them in jars with fish (so that the fish in the bank will not die)
4. wash filter
5. Take out all large things from the aquarium (shells, stones, pink decorations)
if there is a feeder, it is also necessary to rinse it thoroughly, since the sun's rays are now hot in the aquarium and it “blooms” (ie, brown wood is formed on the glass)
6.Color all the bulky water in the bath or sink
rinse the stones through a durshlak or a sieve. old or dirty sand or stones can be thrown away, then bought in the store are new and placed in an aquarium (but the store filler for the bottom should be washed)
7. There is dirt or "mold" on the walls of the aquarium.
8.Rinse the aquarium from the soap.
9.In a clean aquarium, place washed stones (soil or sand) with this large items.
10.If there is a shortening of water on the bottom, it is also necessary to fix.
11. Pour into the aquarium already clean water.
12. Place and turn on the compressor or filter.
13.If you poured into the jar where there is all this fish time:
a) -pure water, it is already worth pouring the whole bottle of water and fish into the aquarium
b) -dirty water from the aquarium, it is already necessary to substitute a net or a sieve pouring dirty water through a sieve or a net, it is necessary in a separate bowl or sink. that is, so that dirty water (from a dirty unwashed aquarium) does not get into a clean aquarium.
14.If you have filtered and defended the water, you should not wait 24 hours to place fish there (to say that when a fish spends a long time in the bank it can be blind because the bank is round!
15. After washing the aquarium, feed the fish.


My mother-in-law changes the water like this: it takes a tube, slightly pulls the air in and the water will flow like a vacuum cleaner removes all the garbage, greens and waste products of your fish !! ! And the fish are not afraid of it !! !
Then pour clean, separated water in a thin stream !!! !
good luck !!!!

Konstantin Shaly

Water in aqua does not change, and 10% per week, or 30% per month, is substituted for beginners. And the white fluff is from peri-abundance of feed, it is rotten. You didn’t complete the aqua launch, planted the fish and began to feed it, therefore, and dregs. Stop feeding, collect decaying organic matter from the bottom with a siphon and the balance will gradually establish itself. Yes, and stop turning off the filter at night, it should work continuously, otherwise it does not make sense.

Elena Gabrielyan

Water for substitution should be fresh from the tap only to defend it should be no less than a day (preferably 2 days) for the volatilization of chlorine. It is impossible to change the water completely. By this you will make a complete restart of the aquarium and disrupt the biological balance, which will have a very bad effect on its inhabitants. It is necessary to replace 1/3 of the volume of water with a thorough siphon of the runta 1 time per week. Mud and fluff in the aquarium from the feed - do not feed the fish for 2 - 3 days (they will survive), do not turn off the filter, biological balance will be established and the water will become transparent.


Already nothing to answer, the last two answers all said. The only thing is to monitor the water temperature when refilling, first bring it to the temperature of the water in the aquarium, otherwise there may be an outbreak of diseases in fish.