I sort of doubt that ammonia caused last yrs fish kill, but I'm not saying it couldn't happen. An oxygen shortage in that shallow water body more likely killed last yrs fish. Elevated ammonia concentrations (total ammonia conc) should result in a phytoplankton -plant bloom unless Phos or alkalinity are limiting factors.

Ammonia can sometimes (not often) become somewhat elevated in early Spring before the denitrifying bacteria and-or phytoplankton can get it under control. Retest after water warms to verify elevated concentrations. Be sure to test water promptly after collection and properly. Be aware of chemical interferences.

As pH or salinity (total hardness) rises ammonia tends to be more toxic. If you truly have valid high levels of ammonia, I think it would be easier to fix the source than try to mediate the elevated ammonia concentrations. I suggest one look for the source or cause that should be fairly apparent and find a way to abate it. Most non-fish production ponds can usually handle normal ammonia production. Firstly you need to verify that ammonia is truly high and your values not a false readings.


What are your current water chemical parameters of pH, alkalinity, T.hardness, ammonia and transparency for this pond?

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