subject: Koi Filters and Koi Pond Maintenance [print this page] Koi Filters and Koi Pond Maintenance Koi Filters and Koi Pond Maintenance
Efficiently managing your koi pond means managing water quality. It is critical that you know the volume of your pond. With that information and a good testing kit, you can effectively determine pond water quality. Essentially, the goal of a koi filter is to eliminate ammonia. To do this, there must be adequate aeration, water movement and substantial growth of nitrifying bacteria and Nitrosomonas bacteria to convert ammonia to less toxic substances. Separate tools or products are needed to accomplish each element of good management. Koi filters alone are not adequate.
Adequate Aeration
Aeration in the pond is necessary to put oxygen into your pond. The water surface gets oxygen from the air so the goal is to increase the surface area by moving the water and creating bubbles. Waterfalls, fountains and bubblers are all useful for increasing the water's oxygen content. Aeration not only increases the water's oxygen content, but releases gasses such as ammonia. If you have left the fountain off for a while, you may notice a "swamp" smell right after the fountain first starts back up. What you are smelling are the gasses that have accumulated in the bottom of the pond while the fountain was not running. The gasses are created from rotting vegetation and other organic materials in the pond. Aeration actually serves two purposes: oxygenating the water and releasing gasses.
Water Movement
Aeration moves water to some extent but water movement can be increased with pumps designed specifically for that purpose. The moving water not only discourages excessive algae growth, but is also good for the fish because it gives them a current to swim against. There should also be spots in the pond that have a very mild current for times when the fish want to rest.
Getting Rid of Ammonia
Ammonia is created as a result of decaying organic matter and from the waste the fish produce. It is easily the number one killer of koi. Managing ammonia in your pond is absolutely critical.
There are three steps to breaking down ammonia. This is accomplished by colonies of bacteria that are encouraged to grow in your pond. Step one is Nitrosomonas bacteria which metabolize ammonia. These bacteria turn the ammonia into nitrite. Nitrite is as toxic as ammonia. The second step is handled by Nitrobacter bacteria which feed on nitrite and convert it into nitrate which is less toxic than the nitrite. These "good" bacteria live in the biofilter, on the fish, on the sides of the pond and many other places in an established, balanced pond. Nitrates are metabolized by most plants which is the third and final step of breaking down ammonia. Blue-green algaes metabolize nitrates in great quantity. Ammonia in general can be controlled by removing brown algal growth from the pond bottom. Changing 10% of the water daily until the ammonia and nitrate levels are reduced to under 20mg per liter is an effective strategy against ammonia build-up.
Designing and building your koi pond to manage ammonia, be beautiful and restful and to provide a rich environment for your koi is not difficult. It just takes planning, consistent koi maintenance and a good pond building guide.