Derek Broughton wrote:
Altum wrote:

How can something that contains ammonia not be toxic to fish???

The fertilizers mentioned contain ammonium, not ammonia. Really close, but
_much_ less toxic.

Ammonium is just the protonated salt form of ammonia.

NH4+ -- NH3 + H+

Put it in alkaline water (as in most ponds) and it promptly loses a
proton and becomes ammonia.

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