Koi & Fish Pond
Koi & Fish Pond
When we think of water quality in our water gardens and garden ponds we usually think of two things: the water's ability to support aquatic life and its clarity. Lack of clarity is usually not a problem for aquatic life, but limits our ability to see and enjoy our koi and goldfish.
The pond owner should be concerned with both of these aspects. While it is true that you can keep fishes in garden ponds with no filtration, it severely limits the number of fish you can keep. In the wild, fish have large amounts of water so that toxins from their waste do not build up to dangerous levels. Most hobbyists will want to keep more fish than their garden ponds will naturally support.
Goldfish and koi excrete waste into the water in the form of ammonia, primarily through their gills. Also adding to the problem are organic compounds from fish feces, plant matter, and soil that may flow into the pond. In order to provide good water quality some form of waste removal must be provided. Two methods used in average water gardens and garden ponds are mechanical filtration, and biological filtration.
Do All Ponds Need Filtration?
No. If you are intending not to have any fish, or you’re creating a wildlife pond with high plant stocks and just a few fish you may choose not to have a filter, and try to create a natural balance instead. It is a relatively simple process but can take a very long time to get a balanced nitrogen cycle within your pond, hence why most people still opt for a filter of some kind.
The principle is very simple.
You will need plenty of plants, probably covering two thirds of the pond area. These plants, along with naturally occurring helpful bacteria in the pond, will then use and digest any toxins left by fish and rotting organic waste, hopefully providing a good natural balance and a clear pond. It is important to remember that the plants should be well established before gradually introducing fish, and it could take at least eighteen months to create a naturally balanced pond.