Why fish tanks foam up?

Answer 1

Foam on the surface typically means the filtration is inadequate. The tank is polluted. The foam is caused by proteins that are not being removed by the filter.

Either increase your filtration (this may just require cleaning the filter), or

reduce the number of fish and other aquatic animals living in the tank.

Frequent water changes (15-20%) per week can help avoid protein foam problems.

Answer 2

Something is wrong! Aquarium water should not be frothy. I would assume some kind of polutant is definitely in there (maybe ammonia?) I would replace the water ASAP. Check for dead fish, left over food stuffs going rotten etc and make sure the filter is working properly. Something is wrong! Aquarium water should not be frothy. I would assume some kind of polutant is definitely in there (maybe ammonia?) I would replace the water ASAP. Check for dead fish, left over food stuffs going rotten etc and make sure the filter is working properly.

Answer 3

If your fish tank is foaming up you have poluted water. There are a few basic rules all successfull aquarists live by. They are "1 inch of fish needs a minimum of 1 gallon of water." " Every fish tank containing life must have a cycled filter." and "Every fish tank needs to have at least 50% of its water changed every week." If you stick to those rules you will have very few problems.