Why does the water in the fish tank stink


Smells the water in the aquarium

Beautiful and harmoniously located in the room aquarium can be a decoration for any interior. Aquarium - a great way to relax and achieve internal balance. However, the fish themselves and their house need constant and competent care. Beginners and even experienced aquarists often encounter undesirable and unpleasant situations that are the result of improper or inadequate care. One of these situations is when the water in the aquarium smells unpleasant.

Let's try to find out why aquarium water smells, and what actions you can take to eliminate unwanted odors from the aquarium.

Causes of smell from the aquarium

With a situation where water smells unpleasant or even stinks, I come across, perhaps, every fan of aquarium fish. The causes of this phenomenon may be different:

  • Aquarium has not been cleaned for a long time. If you do not know, the dwelling for fish and other underwater inhabitants should be periodically cleaned, washing both the soil and algae and the glass of the aquarium. It should also regularly change the water. The smaller the aquarium, the more frequent cleaning it needs.
  • Poor quality fish food. Overdue feed can easily lead to rotting bacteria in the aquatic environment and in the soil. If you find an unpleasant odor in a relatively clean aquarium, try changing the type of food - if the problem disappears, then it’s a matter of poor nutrition.
  • Excess feed. Food is quite normal, but it is possible that you give it in excess. Feed particles that are not eaten gradually settle to the bottom and turn into the ideal substrate for the reproduction of microorganisms.
  • Overpopulation of aquarium. Such a problem is often encountered by novice aquarists who try to fit as many fish of various sizes and species as possible into a standard tank. It should be remembered that the aquarium is a kind of closed biosystem, which must be in harmony and balance. If the house has more residents than it should be, inevitably problems arise with the cleanliness of the premises.
  • The presence of some specific plants. Some types of algae can produce a peculiar smell. It is better to immediately clarify this point during the purchase of plants in the store. Again, the smaller the capacity, the more noticeable the vital activity of plant organisms: in a large volume of water the odor from algae is leveled.
  • Ground souring: methane release by soil bacteria.
  • Lack of oxygen. Deficiency o2 need to be removed with the help of a special device with the function of air circulation or a conventional compressor. Constantly high oxygen content in the water does not allow bacteria of the anaerobic type to multiply rapidly.
  • Too bright light. The abundance of radiation can lead to the multiplication and growth of unicellular algae, which, in turn, can produce unpleasant odors.
  • Too dim light. The lack of radiation causes the active growth of other algae, which also adversely affects the state of the water.

So, in most cases, the unpleasant smell of water is a consequence of excessive activity of putrefactive bacteria or plant organisms. Therefore, the main task of an aquarist is not to allow microorganisms to multiply too intensively, and for plants to bloom too much.

How to eliminate the unpleasant smell in the aquarium

Suppose you figure out why the water smells in an aquarium. What measures should be taken to eliminate this problem?

The first thing you can do is to carefully clean the aquarium with all its contents. General cleaning is carried out according to certain rules. It is necessary to consistently clean the walls, bottom, stones, algae and all other elements of the home for fish. Rotted algae and excess plants should be removed.

Replacing the water in the aquarium is carried out gradually - it can take 5-7 days. A complete and simultaneous change of water is carried out in exceptional cases: it is a huge stress for fish, which can lead to the death of fry and especially sensitive species.

Other methods of combating an unpleasant odor are saturation of water with a sufficient amount of oxygen, changing the feed or regulating its amount, ensuring the optimum amount of light emission. If the aquarium is overpopulated, a part of the inhabitants should be transplanted into another container, sold or donated: it is better to lose some of the pets than to constantly face the problem of the abundance of feces and harmful bacteria. In an overpopulated aquarium, fish feel uneasy and often show aggression towards each other.

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How to get rid of the smell in the aquarium

Some novice aquarists are faced with this situation: recently changed water suddenly begins to emit a whole bunch of unpleasant odors. The solution to this problem depends on the cause of the stench, and there may be several ways out.

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1. The first thing that can be done is to thoroughly clean the aquarium and everything that is in it (stones, shells, decorative castles, houses, etc.). Rinse the inside of the glass well, as even if at first glance they seem to be clean, they may still have a slippery water stain on them. If a few days later from the aquarium again smells unpleasant, you need to look for more reasons in more detail.

2. First, determine which smell comes from your tank. If it smells a bit of mud or swamp, you can calm down. This fragrance means only that everything is in order with him and his inhabitants. This aquarium should smell like a river.

3. If you feel completely different unpleasant odors - rotten eggs, onions or garlic, you must take decisive action. The smell of onions can produce some aquatic plants. For example, if in your aquarium cryptocarins live, there may be such a smell. In this case, add to them a pair of ambulium bushes, a little hornpole, and a few hemianthus bushes. Unpleasant aroma should disappear.

4. The cause of the unpleasant the smell there may be impurities that accumulate at the bottom of the "pond" - this is both the waste products of fish, and the remnants of food. If the aquarium is too large and there is no possibility to wash it completely, just draw a primer siphon. For this purpose, a special device is used in the form of a hose with a tip through which water passes, taking with it all the accumulated dirt.

5. Together with the ground siphon it is necessary to carry out the process of partial replacement of water. This will also help to heal the atmosphere and remove substances harmful to fish. This should be done twice a week, at the same time it is necessary to replace from 20 to 30% of the water in the aquarium. You can use ordinary tap water, but it must be defended during the day.

6. Determine if the fish have enough oxygen. To do this, see if they float close to the surface, gasping for air. In this case, you need to buy a good air compressor, which must constantly work, providing good aeration.

How much and how to defend the water for the aquarium?

Why defend the water in the aquarium for fish, and how much benefit will this procedure bring? Such questions are often asked by novice home-water lovers and more experienced razvodchiki. In fact, settling is a necessary measure to prepare the aquarium for launch, because no matter how much you clean the scenery and glass of the tank, water is its main component, a living environment where both visible and microscopic creatures will live and develop. objects. Therefore, the process of settling involves the study of the rules for the preparation of different types of water.

How to prepare an aquarium with tap water

The easiest and cheapest way to stock up on water is to use tap water in the tank. It is available to almost everyone, suitable for any freshwater aquarium. For fish, it is not harmful if it is properly defended. If a quality water purifier from the tap is not installed in your home, you should not immediately pour the liquid that you have collected into the tank. Compounds of chlorine that are in the water need to be weathered for several days. Why do this? To protect the fish and plants from poisoning and premature death.

You can dial the water in glass jars directly from the tap, and leave it for 3-4 days, covered with gauze. All volatile compounds will evaporate and the liquid will become colorless and free from chemical compounds. It is necessary to check the collected water for smell and color. Chlorinated water smells sharp, has a milky white color.

See how to carefully pour the distilled water into the aquarium.

About water from other aquariums

Water from their other aquarium can be useful - it has a long-established microflora and biological balance. For fish it is a reliable source of trace elements that are beneficial in terms of recovery. However, without knowing the history of another aquarium, it would be correct to find out what freshwater fish lived in it, what it was sick with, and what quality its water was. You can ask this question from the owners of the reservoir, or conduct observations on their own. For the experiment you need only a few days, some free time, and, of course, old water.

Pour the liquid into a clean glass tank, let it stand in it for several days. Noticing cloudiness, precipitation - you know, it is not entirely safe. It is possible to pour a part of such water into an unprepared aquarium with plants. If their appearance has deteriorated - a sure sign that the fish should not live in a pond with such water. But the best way is to start a tank with new water on your own, or to seek help from trusted distributors.

Reverse osmosis and deionization

Settling of water with its subsequent preparation for the aquarium is possible using the method of reverse osmosis and deionization. These are two ways in which you can cleanse and defend a liquid. Each of these processes helps to remove impurities and any particles that may be in the water. Ionization neutralizes pH, eliminating various ions that could remain in the water. However, the resulting water is clean, but potentially dangerous - it does not preserve its biological properties, which is dangerous for fish. No matter how much she praised her crystal purity, she bears the risk because she changed the pH level, alkalinity and hardness.

Deionized water removes beneficial salts and trace elements that are needed for fish and plants. Such water is obtained as a result of deep purification by reverse osmosis, or ion exchange. In the process of pressure, water is passed through a semi-permeable shell from a more concentrated to a less concentrated solution. The shell skips the solution, but does not miss the components dissolved in it.

Sometimes this water is mixed with infused tap water, but you need to be careful.

Watch a video about the reverse osmosis system.

About softened water

Softened water is sometimes useful for fish that need to live in water with certain parameters. Softened water can be obtained for some time, if you defend it 4-5 days, and adding to it the impurities that change the parameters (peat, wood). Softeners need to buy in stores, do not need to mine them yourself. Settling water with the right ingredients will be beneficial for some fish.

What to do with bottled water?

How long should you defend bottled water for an aquarium? She does not require insisting. Bottled liquid, although it is credible, is not useful for fish, because its pH level does not match the standard, and it is free from many trace elements that can “revive” the reservoir. How much such water do not use - even in conjunction with an infused tap it is not very effective. Often, the parameters of such water are completely unknown. Often, vitamins, flavors, preservatives, and even colorants are added to it to maintain a crystal clear appearance. All this is destructive to the health of the fish.

Reservoir with defended rainwater

Rainwater is also used in a fish tank. Previously, such water was used in food, but nowadays it is not particularly useful (except for that which falls in ecologically clean regions). It contains impurities of toxic substances and parasites, therefore upholding and powerful filtration are necessary. Rainwater may contain substances that are not washed out of the air. Pollution from pipes, gutters, pipelines, roofs and other surfaces from which it has flowed into it.

For aquarium needs, rainwater is not always suitable - improper treatment of the fluid hurts the fish. How much time will it take to settle the rain? After drawing water into a clean glass container, install a powerful filter in it, after treating the liquid for several hours. After cleaning, leave the water for a few days in a cool place. However, the risk from such water is high - its application is possible only after laboratory research.

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Why does the water grow turbid in a fish tank?

The aquarium is not only an interior decoration, but primarily an ecosystem that lives according to the laws common to all ecosystems. It is stable when there is a biological and chemical equilibrium in it. An imbalance immediately affects the appearance of the aquarium, and primarily the quality of the water.

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Why does the water grow cloudy?

Turbidity in the aquarium is usually caused by the massive development of various bacteria. Where do bacteria come from? They, like other microbes, enter the aquarium with fish and plants. Their source can also be soil, fish food and even air with which water is in contact. A certain number of bacteria is always present in each of the elements of the ecosystem. In a certain amount, they are harmless to other inhabitants of the aquarium. At the same time the water remains clean and clear. With the mass reproduction of bacteria, you will definitely encounter two or three days after filling the aquarium with fresh water. This is due to the fact that in the absence of a sufficient number of other organisms, bacteria begin to multiply rapidly. Outwardly, it looks like a light whitish or nacreous homogeneous dregs. The process of reproduction of bacteria goes faster if there are plants and soil in the aquarium.


After another 3-5 days, turbidity disappears. This is due to the appearance of ciliates in the aquarium water, which are intensively eaten by bacteria. There comes a moment of equilibrium of the ecosystem. From this point on, fish can be settled in the aquarium. Plants need to be taken from an aquarium with healthy inhabitants.

Organic slurry

The clouding of the water in an aquarium where there are already fish can be caused by an organic slurry. The suspension is formed from the waste products of fish and plants, as well as improper feeding and an excess of dry food. To control the suspension, aquarium filters are used, including biological ones, in which organics are actively absorbed by bacteria living on the filter material. Mandatory measures are also cleaning the bottom, removal of dead parts of plants, dead organisms, excreta.

Imbalance in the presence of fish

The rapid turbidity of the water in an aquarium with living fish can be a manifestation of an imbalance and may be the first symptom of the disease of the entire ecosystem. For example, precede the blooming of water. In this case, the aquarium has a large volume, frequent full change of water in it is impractical. It is easier to restore biological balance by adjusting the light mode and replacing only part of the water. In large aquariums, biological balance is easier to maintain than in small ones, but it lasts longer. Branching crustaceans (daphnias, moinas, basmins, etc.), which feed on bacteria, are good feeds for fish are good sinkers of dregs. A mandatory equilibrium factor should be considered aeration and filtration of water. Filters should be cleaned regularly.

How to make crystal clear water in an aquarium?

To make the water in the aquarium crystal clear, as in a public or store pond for fish, you must achieve a certain level of transparency in various ways. Very clean, almost blue water is a liquid without turbidity, dirt and harmful impurities. In such an environment, any decorative pet will feel safe, demonstrating health and beautiful appearance. New aquarium, or old - it does not matter, it is better to wash it thoroughly and clean the water. There are conditions, the maintenance of which will make the aquarium water crystal clear.

Original purity

Чтобы получить прозрачную воду, нужно сделать уборку резервуара с помощью поваренной пищевой соли - она нейтрализует бактерии, стеклянные стенки обретут блеск. После мытья сполосните емкость водой из-под крана, используя шланг.

Поместите в аквариум темный грунт крупного размера - он превосходно оттеняет цвет рыбок, в отличие от светлого грунта. Поскольку некачественный песок и камни могут быть причиной загрязнения воды, грунт следует перебрать, удалив из него органические примеси. Затем промойте песок до тех пор, пока вода не станет прозрачной. И последний шаг - прокипятите его и еще раз промойте под проточной водой. Это касается песка речного, а не купленного в магазине. Store sand is already cleared of pollution. It should be laid in a layer of 4-5 cm.

  • Do not fertilize the soil with peat, clay, silt, chernozem and other fertilizers! It will pollute the pond.

How to plant plants correctly

For water transparency, it is desirable to plant simple-to-maintain plants that do not pollute the water space and take root in the new soil. Among them:

  • Hygrophilus;
  • Fern ceratopteris;
  • Vallisneria;
  • Peristuphrium;
  • Ludwig;
  • Sagittarii;
  • Ambulia

See how to plant aquarium plants.

Plants are recommended to plant bushes of the same variety - so they grow better. Vallisneria can not be planted next to other species. In order to avoid water turbidity, first plant the plants, and then add water to the tank. Seedlings should be placed in the recess, dropping the roots into the ground, and filling them with sand.

About the scenery

The purity of the decorations in the aquarium also affects the quality of the water. The rules that are best to follow when installing jewelry in a container:

  1. All decorations (grottoes, caverns, coconuts, snags, castles, labyrinths) should be treated from dirt and parasites in infused water (leave them for 3-4 days).
  2. If you decorate the bottom with stones, let them be red or black. However, the stones must be washed carefully, it is desirable to boil them. Calcium and magnesium in the stone which increase the hardness of the water spoil the parameters of the reservoir.
  3. Put the stones in the poured water so that they "got accustomed" there.
  4. Cover the aquarium - as long as the fish do not live in it, it will be saved from dust and insects, and a film of cyanobacteria will not form on it.
  5. After installing the decorations, run the fish in 2-3 days until the water in the aquarium settles, establishing biological balance.

Read more: Coconut in an aquarium - what you can do with your own hands.

See how to prepare a snag for an aquarium.

The secret of the purity of "residential" water

Many novice aquarists make a mistake when, after the first days of launching the reservoir, they begin to worry about the formation of mud and foam in it. It appeared bacteria that got into the aquatic environment from the air. Then the owners of the aquarium begin to change the water and do other procedures with it. It is better to wait 5-6 days, and the clouding will disappear. Otherwise, there really is something wrong with water.

Having been patient and waiting for 6 days, you will find clear and slightly yellowish water in the tank, which in professional circles is called “living”: infusoria and organic substances appeared in it, but there are almost no bacteria, neutralized ciliates.

Such water is a guarantee of health in an aquarium; it can be completely not changed for several years. If this water is renewed by more than half, bacteria will appear in it, causing turbidity.

Water Purifying Filters

Known so-called "live" and "inanimate" filters that help clean the water from pollution and bring it into a beautiful view. For aquariums install mechanical filters with a cassette and a sponge. However, once in the store where the fish are sold, you noticed that they swim in an ordinary tank, where there is no filter. It turns out that it is possible to maintain perfect purity without mechanical devices, sometimes their constant use brings harm. If there is no such filter in the aquarium, it means that it has a biological filter.

Biological, that is, living filter - these are plants that are planted in a lighted place. Infusoria and microwells that feed on bacteria are well developed in them. Thickets also keep dirt and turbidity in the aquarium with their stems and leaves.

Excellent "filters" are bottom fish (catfish) and snails that eat carrion. Based on the observations, the cochlea is able to make the water absolutely clean in a matter of days. This is probably the most affordable "filter" for a tank of water. Just be careful - some species of fish and amphibians are not averse to eat it.

One more representatives of the underwater world who are able to clean the environment in an aquarium are clam clams. Pea and sharovka love warm water, and toothless and perlovitsa - cold. Unfortunately, like snails, these mollusks can be eaten, so before putting them into the tank for "cleaning", it is better to evict the rest of the pets from it. Also, the larvae of toothless and perlovitsy parasitize on fish. Most likely, after cleaning the reservoir, you will have to quarantine the aquarium.

Spur frog - vertebrate amphibian, which will bring the aquarium to transparency. She can constantly live in the nursery with small fish, in parallel helping the water to be updated. The frog always lives in the water, but if it brings in fry - and there are a lot of them, the aquarium "jungle" will not rest. Carefully monitor the parameters of the water in the aquarium: regularly update the water, plant the correct plants, settle the “orderlies” into it, then he will get a wonderful appearance and a healthy balance.

Why is the water in the aquarium muddy and stinks?

User deleted

In general, there are a lot of reasons why water will deteriorate ... Improper lighting too much food is thrown into the water by the absence of filters in an aquarium, bacteria, etc.
For the night, the aquarium should be well treated first, then cleaned with boiled salted boiling water, the whole grund is boiled well in salt water, the algae should be examined if they are not bright green, not damaged, see if they are black dots if there is easier to throw out and buy New to heal, knowledge is needed, and you, I assume, are new to this, fish should be fed no more than once every 3 days and the food that you feed should be eaten in a minute and not set on the bottom of the aquarium and rot ...
after treatment, water must be poured at least 24 hours in the distance ... at least ...
Go to the pet store buy AKUTAN, this is a blue liquid, add it to the water at the rate of a cap of 10 liters ... and then run the fish for 3 days, the water will have a slightly white turbid but within 3 days it will change ... and the aquarium should stand in a dark place but have a good daylight lamp ... and do not forget about the number of fish at the rate of 1 fish 3-5 liters of water Ie per 10 liters of water no more than 2-3 fish of average size ... if possible, there should be a filter pump water should circulate and clean constantly good Other filters have cells for adding coal to ceramics. Well, they will tell you about this at the pet store, and so good luck, and if you ask anything ...


Apparently, either pour water not previously defended, or algae are bred there.
With algae can fight. There are water snails that devour them.
And be sure to plant a water in the water - a crochet - sold in the market. A plant that protects water from "dirt."


Perhaps the filter does not work well or something got started there that it is difficult to remove it just by changing the water. It can be algae (small ones at all) and then you need to buy in the pet store a means to combat such algae. Or just try again not just to change the water, but even boil the soil and boil over everything that you have installed in the aquarium


damn, well, what are you ?? ? Why change the water then ?? ? it is so necessary! You see, you probably planted the plants there, so from the plants of day 2, the water must grow cloudy, and then everything will pass !! ! and do not change the water so often !!!! it is generally very rarely changed, and the fish will die then ... everything is fine with your aquarium


maybe you have a lot of fish and the aquarium is small. 1 liter of water 1 fish about. Try boiling pebbles all, maybe there are bacteria that bred and multiply very good. quickly, water poured into the aquarium. but in general, the smaller the aquarium, the more worries with it !! ! It very often needs to be washed. but if it becomes cloudy in one day, then you need to look for the cause, and the fish do not die ???

* N *

In the aquarium, fish need oxygen, a water filter, and even the water does not like a lot of light (it starts to bloom).
If there are pebbles and shells, they should be boiled, water should be boiled and water should be poured and boiled again for 2 hours, the aquarium should be washed with soda, the plants should be washed thoroughly. Before you pour water into the aquarium, you need to defend the water for 3 days, then pour it into the aquarium, then put oxygen into the water and after 20 minutes you can let the fish.

User deleted

The tank should be at least 25 liters. Otherwise, it will not be an aquarium, but crap! There necessarily need a filter and pump (bubbles). Sunlight should not be on the aquarium. Fish should be fed 2-3 times a day in small portions. Water changes no more than 30% at a time. Immediately start the fish can not be! It is necessary to first establish a biobalance. (about 4-5 days). Generally dig a good internet! You probably first have fish, then an aquarium, then plants, and then food. all the way around!

Why does the water in the aquarium stink a swamp?

Natalia A.

And it will stink until the right to start the aquarium, in which the fish sits down after establishing biological balance, and not before. Materiel teach. The displacement for a couple of asters what? You need at least 250 liters for them with a pair of good filtration.

Anastasia Life

the ground has nothing to do with, do not completely change the water, the filter must be sure that the water does not stagnate, it is necessary to feed properly: throw the bloodworm little by little so that it does not fall to the bottom, and for the catfish it is better to buy special food, vipagran, it is very convenient with balls.

Alexander Ognev

Read about the launch of the aquarium and find your mistake. the main thing - do not be lazy to read. what kind of catfish? a lot of soms. You can have a peaceful Ancistrus catfish growing up to 10cm. or a red-tailed catfish, devouring everything that crawls through its huge mouth and grows up to a meter. a couple of astronotus at least 200 liters, the fish grows up to 35 cm.
it is not necessary to boil the soil, about boiling the soil is complete nonsense.

Evgeniya Yarovaya

Fully agree with Alexander, Well, astriki are corpses 100% Everything is done and wrong, you must first start the aquarium. for a week it should stand with water and the filter turned on, after one unpretentious fish sits down for a week, it will help you establish the nitrogen cycle, then quietly run the fish two times a day, the Astrika Naparu needs at least 200 liters, it’s a very large territorial fish ? Of course, you don’t have a balance. Feed your favorite fish "from the belly". In short, you want to save. Do the following to replace 30% of the water with a siphon of the soil; volume, fish do not feed at all for three days! She does not poploheet! Do not be afraid, twice a week it is necessary to replace water at 20% per cent of volume every month! Then you can carry out this procedure rvaz per month but definitely!

Rus White

The smell from the aquarium is caused by the presence of rotting organics. Put a good exterior, you can biofilter, adjust the water change mode, clean the bottom in time, do not overfeed the fish and do not overcrowd the aquarium


My aquarium is overpopulated. (not my fault :)))))) all summer the fry were born, but it’s a pity to give) the soil is boiling periodically. Water is changing. Filters ... everything is fine. But it stinks of swamp. Because of the soil, I think AND MORE. Because of the snails.

Why does the water in the aquarium grow cloudy and stink?


Oh, what a horror they wrote to you (Stop changing the water, it is changed every six months with a non-overloaded aquarium or once every 2 months ~ 25% when overloaded) and aquarium plants called algae could be written by a person who clearly does not understand what an aquarium as a whole is.
Do not try to follow this advice.
It is necessary to deal with the problem.
1. What is the displacement of water?
2. what is the population.
3. when the aquarium is running
4. Which filter and which fraction is the soil?
5. How often do you siphon a primer and change the water?
6. Where is the aquarium, do the direct sun rays fall on it?
7. Look attentively, maybe in aqua something is rotting (snags, corpse of fish or snail).
Obviously you have a lot of organic matter in the water, now to stabilize the water, you will need daily water changes of 30% during the week (with a mandatory siphon of the soil), it is advisable to add sulfur nitrivek, the filter is mandatory at least internal, feed the fish once a day to a minimum (feed should be eaten in a couple of minutes).
Never wash the aquas completely (only in critical situations), water changes should take place once a week for 25-30% of the total volume with a siphon of the soil and washing the filter (sponge). Review the population of your tank, you may have too many fish for your volume.
And read to start carefully

Elena Shmakova

The water in the aquarium is turbid. Why?
If the water is whitish with a smell like a toilet (ammonia).
Usually happens if you:
1. Cleaned the aquarium recently.
2. Changed the water.
3. Launched a new aquarium.
4. Occurs when changing algae or scenery.
5. Too small pebbles (like sand, food sits in the sand).
The reason is that the ammonia cycle is not installed.
Stop changing the water, it is changed every six months with an unloaded tank or every 2 months ~ 25% with a congested one. If you stop interfering in the cycle and feed the fish once a day, in the morning or in the evening, the water will brighten in 2 weeks.
Another case is when the water is greenish with a marsh smell (no ammonia).
It usually happens if you:
1. Heat the water in the aquarium above 23 degrees.
2. The sun heats the water above 23 degrees.
3. Incandescent lighting heats the water above 23 degrees.
4. You just overdo it with the total amount of lively greens, even if below 23 degrees.
The reason is that algae decompose faster than bacteria process them. Remove to start ~ 40% of greenery and stop changing the water, and change anything in the aquarium (Although if you can seriously replace 25% of the water, but no more, otherwise you will wash all the useful ones). After a week or two, the water should lighten up, you can return the algae, but keep the temperature in the aquarium no higher than 25, otherwise everything will start again.