The good aerobic bacteria colony will adjust its size to the food (ammonia and nitrite) and the availability of oxygen. In a pond in the north that the water gets down into the 30's in the winter the fish's metabolism slows to the point that they are using fat reserves stored in the liver to live. The colony of bacteria adjusts to that level of waste produced as it is the limiting factor. Once the Spring thaw occurs and the fish begin actively feeding again the bacteria colony increases in size as food (ammonia and nitrite)become available.

If the bacterial colony dies it takes 2-4 weeks to establish itself again. During this period you would have ammonia and nitrite spikes probably resulting in some if not all of the fish dying.

If food and oxygen are available the bacteria colony will live through the cold.

*EDIT* The cold water algae is probably getting its food in the form of nitrates from the colony of aerobic bacteria. From what I know nitrates and phosphates are what fuels the algae.

Last edited by Fish Food; 10/30/14 10:31 PM.
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