New Ponds & the Nitrification Cycle

When you first add fish to your pond, it is important to understand the process called the nitrification cycle.  The nitrification cycle is a natural biological cycle that begins when live fish excrete ammonia from their waste and from their gills.  The ammonia initiates a somewhat toxic process where bacteria begin to form and eventually, if the pH is balanced and there is plenty oxygen in the pond, the bacteria colonies become large enough to process most or all of the toxins in your pond.  This bacteria growth process typically takes up to 12 weeks.

Nitrosomonus bacteria begin to grow that help to convert the toxicity of the ammonia by consuming it and excreting nitrites.  Nitrites are eventually consumed by other bacteria, referred to as nitrobacter, and it is then converted into nitrAtes.  Nitrates are consumed by water plants and/or the small growth of algae that occurs on the sides and bottom of your pond, thereby turning the water into potable water that is safe for fish.

Ammonia and Nitrites can be harmful to Koi.  Since they must be in the water in order to develop the bacteria necessary for the nitrification process, you must do something to protect the fish.  To protect from ammonia, use Ultimate to lower to ammonia level to between .05 and .10 and test water frequently to check levels.  To protect from nitrites add non-iodized salt to the pond, bringing the level of salt in the water to .3% and keeping it at that level until there is no trace of nitrites.  Then start gradual water changes of no more than 15% of the volume of the water in your pond, per week to dilute the salt content.  Use 1 lb. Salt per 100 gallons to reach .1%, adding 2 additional doses of the same amount to reach .3% .

Until the nitrification cycle has completed the growth of necessary bacteria:

- Test for Ammonia Daily until it disappears

- Test for Nitrites Daily until it disappears

- Lower Ammonia levels to range .05 - .10 by using Ultimate

- Add non-iodized salt to .3% and keep it there until no trace of nitrites

- Always treat water added to your pond to remove chlorine and chlor amines with Ultimate

- Consider using commercial nitrifying bacteria to aid in the bacteria growth with Ki Nitrifier

Non-iodized salt can be purchased in bulk at Home Depot in the Water Softener section.

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