Previous Questions

What is a biological filter?

The biochemical function of the aquarium filter is to remove harmful substances from the water by biochemical reaction. This means that bacteria within the filter can chemically alter a substance (for example, ammonia) to turn it into something else.

Nitrifying bacteria are responsible for removing the dangerous ammonia and nitrite that are produced by fish as a waste product. They do this by changing the chemical composition of these toxic substances, resulting in the formation of nitrate. Nitrate is relatively harmless to fish, and can be easily removed through water changes and by live plants, which use it as a food source.

Once a filter has been established in a tank for several weeks, it becomes ‘mature’, meaning that there are enough bacteria in the filter to cope with the amount of waste produced by fish. If a tank is overcrowded, then problems will occur because the filter will not be able to cope with the large amount of waste.

In new tanks, the filter is not mature, meaning that it has not built up any bacteria. New tanks should be cycled by adding King British Filter Aid + without any fish in for at least two weeks before adding fish. When adding fish, it is best to add a few at a time to allow the filter to mature gradually, otherwise the amount of waste will overwhelm the filter and as a result fish may die from ammonia or nitrite poisoning.

King British Filter Aid + can help to overcome the problem of ammonia and nitrite poisoning in aquariums. It is a unique blend of nitrifying bacteria, which, when placed into the aquarium, ‘seeds’ the filter with bacteria.