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Fish Tank Aquarium Problems – No 2 Cloudiness

In the article I’m going to tell you about Fish Tank Aquarium Problems – No 2 Cloudiness.

Fish Tank Aquarium Problems


Cloudiness is not unusual in a newly set up tank and will usually go away on its own. Don’t start adding chemicals to deal with it. It is caused by the increase in bacteria that are free floating for a while until they settle on decorations, gravel or the glass. The bacteria are ones you need to encourage to deal with the waste products from the fish. If you have properly cycled the tank it should clear in two weeks at the most. In a new tank it is essential that you do not overfeed as there will not be enough bacteria to deal with rotting food.

After two weeks or in an older aquarium the cloudiness will be from a different cause. Bacteria bloom is caused most often by overfeeding which allows a build up of nutrients in the tank for other types of bacteria to grow out of control. high levels of nutrients in the tank provide ideal conditions for all sorts of other bacteria to grow. The bacteria will not actually harm the fish but are a sign that the levels of toxic chemicals in the tank water are too high.

An overgrowth of algae, an algae bloom, is another cause of cloudiness. Algae blooms are sometimes distinguishable form bacteria blooms by a slight green colour. the algae will be trapped in a diatom filter so if you have this kind check to see if there is a build up of green material on the filter. If you can’t decide if it’s an algae bloom or a bacteria bloom follow the treatment below to deal with a bacteria bloom.


For a new tank do nothing! Wait for two weeks to see if the cloudiness will disappear. Make sure you are not overfeeding and remove any uneaten food on the bottom with a siphon. For an older tank or if the cloudiness doesn’t disappear in two weeks make a 30% water change. Remember never to do a full water change! wait two days and if it hasn’t cleared you probably have an algae bloom. to reduce the level of algae turn off the light and keep it off for at least two days. Don’t feed the fish during this time. It really won’t harm the fish at all!


To prevent these problems occurring in the future make sure you maintain your tank properly. There are very few times when chemicals are needed and often they will make the problem worse. Resist the impulse to go straight to the local pet shop and buy them! In the pet shop they are there to make money of course and will probably not give you advice that you can apply for free.

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