Aquarium water becoming cloudy is one of the most common problems faced by aquarists. If you’ve had a lot of time in the hobby, you’ve certainly been through it countless times. The whitish or cloudy water, in addition to the visual impact, can mean that your aquarium has some imbalance, and can even affect the health of your animal. However, in most cases it is an easily solvable problem. But after all, what can make the aquarium water cloudy?
An aquarium with cloudy water usually has excess decomposing organic material or imbalances in the bacterial colony (eg from incomplete cycling). These factors cause an uncontrolled proliferation of heterotrophic bacteria and it is precisely this increase that causes the water in your aquarium to become cloudy.
Cloudy water, although not an emergency situation, also has its dangers. These bacteria in excess consume the tank’s oxygen, and can asphyxiate the fish depending on the amount of air dissolved in the water. In addition, proliferation is already a sign that the water quality is far from ideal, which is already enough to cause diseases and affect the immunity of your animals.
Common causes of cloudy water in the aquarium
The bacteria that cloud the aquarium water, can only reproduce uncontrollably due to the excess of polluting substances (which are nutrients for the bacteria) dissolved in the water. This happens for several reasons. Some of the main ones are:
Uncycled aquarium: One of the worst decisions an aquarist can make is to skip an aquarium’s cycling period. As annoying as your aquarium is unpopular in the first month, the benefits are proven and easily observable. So, if you haven’t cycled your aquarium, this is probably the main factor that generated your dirty water. Also, during the cycling period it is completely normal for the water to become cloudy. So if you are cycling your tank (no fish), don’t worry, over time the water will return to crystal clear.
Insufficient filtration: Every aquarium needs a good filter (there are some exceptions in heavily planted aquariums). If your filtration isn’t enough, your aquarium’s ammonia and nitrite levels will inevitably rise. Over time, the concentration of these compounds can become so high that they cloud the water and harm your fish. Bad filtration can have several reasons, such as: bad brand filter, low flow, lack of biological filtration, etc.
Decaying fish and plants : Another cause of pollution that can cause water to cloud over is the presence of decomposing elements in the aquarium. Excess of dead plants, leaves thrown by the substrate, or especially decomposing animals can greatly increase the level of dirt in your tank. It is not uncommon in aquariums with many hiding spots, that some fish when they die are holed up or even that the water flow takes them to these hidden spots. When this happens, the fish can decompose for a long time, without attracting the aquarist’s attention, thus generating a total imbalance in the parameters of your aquarium.
Overfeeding : A very common mistake, especially for beginners, is overfeeding your fish. This excess can foul your aquarium in at least two ways. First, if there are leftovers, the feed settles in the substrate and begins to decompose, with time rotting your water, especially if your aquarium is small. Second, even if your fish have a lot of appetite and consume all of their feed, it can speed up the digestion process, thus increasing the amount of droppings in the water and this waste is some of the biggest contributors to aquarium pollution.
Overpopulation of fish: An overcrowded aquarium is a dirty aquarium, this is an undeniable law. The main factors that limit the amount of fish you should have in your aquarium are your aquarium’s liter and filtration. The more fish, the bigger your aquarium should be. And the larger the aquarium, the greater the need for a powerful filter. Also, if you approach the limit of fish per liter in your aquarium, you need to have an even more powerful filter than normal to compensate for this exaggeration.
Poor quality water in the aquarium : Sometimes the source from which you are collecting your aquarium water can be dirty. In that case, no matter how much you care for your aquarium, it will never be enough to clean water that has already been added dirty. This is very common in areas without water treatment or during a water crisis.
If your aquarium falls into any of the above situations, sooner or later, it will suffer from problems. Cloudy water is even one of the least serious.
How to make your aquarium water crystal clear
To get rid of the cloudy water in your aquarium and have crystal clear water again, we need to focus on cleaning your aquarium, that is, zero ammonia and nitrites and establish stable, quality water.
Test your aquarium water: Check your aquarium’s ammonia and nitrite levels before, during and after treatment. This will give you more understanding and control over your aquarium parameters. Remember that the goal is to zero the concentration of these elements.
Complete Aquarium Cycling: If you are setting up your aquarium now, cycle the aquarium all the way through and without fish. In this case, do not be alarmed by the cloudy water and continue, as the cycling progresses, the water becomes crystal clear. If you already have an aquarium set up and with inhabitants, you can do fish cycling, it is not the best option, but it may be the only one if your tank is already set up.
Use a suitable filter: As stated earlier, choosing the right filter for your aquarium is critical. Therefore, always choose good brands (this is not the time to save) and filters that cover the need for mechanical, biological and, if possible, chemical filtration. It is also important to be concerned about the flow rate of the filter. In general terms, filters need to have an hourly flow of 5 to 10 times the volume of the aquarium
Keep aquarium clean: Make sure to clean your aquarium. Do a 50% TPA and then maintain normal TPAs of 15% to 25% every week. Daily remove any visible dirt buildup in the aquarium (plant remains, dead fish…). Check the most hidden spots in the aquarium to ensure that no dead decaying animals are rotting the water. Also, maintain your filter regularly.
Do not overfeed: Do not overfeed your fish. Never. If you have leftover food in the aquarium, you are definitely overfeeding your animals. In addition, prefer to divide the feeding in more than one time. It is preferable to give small amounts of food two to three times a day, rather than a lot of food, just once.
Adapt the fauna of your aquarium to its literage: There is no perfect rule to measure how many fish should be placed in an aquarium, it depends a lot on the person’s common sense and experience. But there is a rule that aquarists often use as a guide at these times.
The cm rule: The rule says the amount of water needed according to the length of the fish:
Fish 2-5 cm -> 1.5 L/cm
Fish 6-9 cm -> 2 L/cm
Fish 10 -13 cm -> 3 L/cm
Fish of 14 cm or more -> 4 L/cm
Test your home water: The same ammonia and nitrite tests that are done in the aquarium can be done on your home water (remove the chlorine first), so you can know if this is the source of your aquarium pollution. If so, you may need to get another source, or use a deionizer to produce truly pure water.
Is it worth using products that promise to make the water crystal clear?
There are products that promise to leave the water crystal clear overnight, or even in a few hours. While it is possible for them to work in the short term, they do not treat the cause, only the symptom. Then the problem will return if you don’t take care of your aquarium water as mentioned above. Also, depending on the substance used, these products can even harm your aquarium’s biology.
Alternative causes for clouding water
Other causes such as new substrate, medicine and extreme substrate movement can temporarily cause cloudy water due to suspended particles in the water. Generally, this type of clogging clears up on its own within 24 hours if you have an efficient mechanical filtration system. In the specific case of medicines and other chemicals, check the package insert or packaging for how long they affect the visibility of the water.