A white cloudiness in your tank is usually a sign that you have bacteria bloom. However, it may be difficult to tell the difference between bacteria bloom and algae bloom, which is greenish in color. One way to distinguish them is to look at the filter material which will usually have a greenish tinge if the culprit is an excess of algae. If you have a newly set up tank you may also experience some cloudiness which will usually go away on it’s own in a few days.
Although you have worked hard to encourage the beneficial bacteria to grow when you cycled your tank they can then start to grow excessively and cause this type of bloom. It can be detrimental to your fish as the bacteria can deprive them of oxygen and if it gets too bad can cause them to die. It is a good idea to always test your tank water regularly for ammonia to alert you to any problems before they get too bad. Another cause of bacteria bloom can be adding medications directly to your tank. It is always much better to have a quarantine tank to place sick fish and treat them there rather than in your main tank.
Clearing Bacteria Bloom
vacuum the gravel to remove any decaying food, take out any plants that are decaying and then do a 30% water change. Never do a full water change as you do not want to remove ALL the bacteria, only the excess. Do not feed your fish at all for a few days, they won’t suffer believe me!. You want to remove any sources of nutrients for the bacteria until they get back down to reasonable levels.
Preventing Bacterial Bloom in the Future
Bacteria bloom is caused by nutrients in the tank feeding the bacteria so that they multiply excessively. You need to keep any excess nutrients to a minimum by not overfeeding the fish and removing decaying plants promptly. Partial water changes every week are recommended and test the water for ammonia at least weekly to be alerted to any developing problems.
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