Page 29 - Koi Net - On-Line Koi Magazine - Issue 1

than in ammonia so the process of using it as their energy
source is far less efficient which explains why the nitrite
bug is weaker and grows more slowly than its cousin, the
ammonia bug. This means that they multiply far more
slowly and, even under good conditions, growing a full
size nitrite bug colony will take several weeks. If ammonia
levels rise too high during this natural maturing process,
the rate at which they grow can be even slower because,
although the nitrite bug actually needs a small amount of
ammonia in its “diet” in addition to the large amount of
nitrite that it uses, its reproductive processes are inhibited
by high levels of ammonia.
During maturation, as the ammonia level rises and
provides the energy for ammonia bugs, their growing
colony size causes a growing level of their waste product,
nitrite as is shown by the orange curve in the diagram.
This doesn’t begin to decline until the nitrite bug colony
has grown in size. When the colony is matured, they will
be able to use all the available nitrite as quickly as the
IS THERE ammonia bug produces it and this produces a growing
level of nitrate in the water. This nitrate isn’t quite as
A BETTER harmless to koi as was previously thought but, at least, it
isn’t very toxic as long as levels are controlled by such
WAY means as water changes, vegetable filters or special
? Is there a better way?
denitrifying media.

When fish are used to supply the ammonia necessary to
mature a biofilter, the process whereby, first the ammonia
level rises then, as it falls, it is replaced by a longer lasting
rising nitrite level until the biofilter has completely
matured, is called new pond syndrome. With very limited
numbers of fish on a very limited diet and with the help of
water changes to keep the levels as low as is possible,
the fish won’t be badly affected. However it’s difficult to
keep levels within acceptable limits and this is the
problem that fishless cycling is designed to eliminate.
Next issue Syd Mitchell examines another option.

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