Biological filtration can incorporate one or more media on which the bacteria will grow.
Whichever media you choose, their function will be to colonize the aerobic or oxygen loving bacteria that oxidize the ammonia to produce nitrite.
The flow rate through the filter must be slow enough to allow the bacteria to do their work.
Nitrite is also highly toxic and should not be allowed to increase in level as it will damage blood cells of the koi, which can lead to internal organ damage.
Even in extremely small concentrations, nitrite is still highly toxic to fish and must be closely monitored.
You may register an increase in nitrite level when a new filter is going through the maturation process or when a mature filter has to cope with an additional fish load.
The next stage of the nitrogen cycle is the colonization of the bacteria that further oxidezi the nitrite to nitrate.
Nitrate is considered less harmful to fish, and keeping the level well below 100 mg/l and preferably less than 50mg/l is recommended for koi.
Although they can cope with higher levels than this for short periods, avoid it is possible.
Because nitrate is a plant food, external vegetable filters can help to keep it under control.
They can also double up as an effective backdrop to a pond or form a stand alone water feature.
Single cell and filamentous algae will also thrive on nitrate.
Pond plants and algae will be eaten by the koi and the cycle begins again.
The nitrogen cycle can best be summarized as follows.
The total ammonia starts at zero with no fish, no plant life, but rises with time when fish are added and as feeding is increased.
Then, the bacteria start to multiply and as their food supply increases, they oxidize the ammonia and the build up of nitrite begins.
Whichever media you choose, their function will be to colonize the aerobic or oxygen loving bacteria that oxidize the ammonia to produce nitrite.
The flow rate through the filter must be slow enough to allow the bacteria to do their work.
Nitrite is also highly toxic and should not be allowed to increase in level as it will damage blood cells of the koi, which can lead to internal organ damage.
Even in extremely small concentrations, nitrite is still highly toxic to fish and must be closely monitored.
You may register an increase in nitrite level when a new filter is going through the maturation process or when a mature filter has to cope with an additional fish load.
The next stage of the nitrogen cycle is the colonization of the bacteria that further oxidezi the nitrite to nitrate.
Nitrate is considered less harmful to fish, and keeping the level well below 100 mg/l and preferably less than 50mg/l is recommended for koi.
Although they can cope with higher levels than this for short periods, avoid it is possible.
Because nitrate is a plant food, external vegetable filters can help to keep it under control.
They can also double up as an effective backdrop to a pond or form a stand alone water feature.
Single cell and filamentous algae will also thrive on nitrate.
Pond plants and algae will be eaten by the koi and the cycle begins again.
The nitrogen cycle can best be summarized as follows.
The total ammonia starts at zero with no fish, no plant life, but rises with time when fish are added and as feeding is increased.
Then, the bacteria start to multiply and as their food supply increases, they oxidize the ammonia and the build up of nitrite begins.
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