tatu
I say one just the other day that was NH4+ but do not remebmer where. I'll rack my brain.
each species can potentially contribute to biochemical processes
Yup and is why it is std
1 mg NH4-N = 1 mg NO2-N = 1 mg NO3-N
True but that is very misleading to a point;
1 ppm ammonia (yields) --> 2.7 ppm nitrite(yields) --> 3.6 ppm nitrate(yields)
Ammonia x 3.6 = Nitrate ppm
Ammonia x 2.7 = Nitrite ppm