Filtration is a key process in fish keeping be it a Bowl / Glass Tank or Outdoor pond or pool. Fish will have a healthy life only in clean and aerated water. In the natural environment like River and lakes, the water is renewed automatically. The Nature does the water cycle by itself. Yes of course humans pollute it most often.
We will talk about aeration in the a different thread. For now let’s stick to Filtration. Biological filtration is the best suited method for fish ponds. In a captive fish pond the ecosystem is closed and hence the water cycle will not happen by itself. Any kind of impurity generated inside or induced from outside needs to be cleared by force.
So there are two parts of clearing these impurities.
- Have a good Filter system
- Partial or full Water change (Need based)
Selecting a Filter System
There is a myth that green water in the pond is not good. Or the Black bottom of the pond means its water is not good. Reality is that some algae in pond is necessary and crystal clear water also doesn’t mean its good. The impurity which is fatal for the fish is ammonia which is not visible by naked eyes and needs testing kits and tools.
How does a biological Filter work
The Basic function of the pond filter is to break down harmful ammonia into Nitrates. This is done by essential Bacteria. Re-circulating water of the pond thru the filter with essential bacteria is the only way to do so. Essential Bacteria is colinised in the filter media inside the Pond filter. These essential bacteria needs to be recharged periodically based on the need. There are many brands which produce the essential bacteria which comes in Liquid and powder form.
Sunsun and Boyu are world famous brands of Pond filter manufacturers. The pond filters come in different size.
While choosing the right model, please ensure that the filter has double the holding capacity of the pond and the pump has half the capacity of the filter. Which means the pond filter should not pull and flush the water in the same flow. The water taken from the pond needs to mix with the filter media and enough essential bacteria should be mixed in the water.
Some of the popular models of Pond filter are SunSun Grech CPF 15000, BOYU Gardening Pond Filter EFU 15000A, Sunsun CUF 5011, Boyu Gardening Pond Filter EFU 10000, SunSun Bio Pond Filter CBF 200T, Boyu Garden Pond Filter YT 6000, SunSun CPF 30000 Pressure Pond Filter, Sunsun CPF 50000 Pond, Boyu Garden Pond Filter YT 25000