Richard Sexton wrote:

frankly it's easier to add potassium nitrate and test for nitrates;
if you have any, you have potassium. in a tank with regualr water
changes
and enough dosing of kno3 to keep plants green you'll neevr run out
of
potassium


This advice has caused me concern in the past, and seems contradictory
to the "accepted" NPK ratio. If KNO3 is roughly 50/50 Nitrate to
Potassium, how do we get a 1:2 ratio N to K without adding additional
K? Especially since we are adding additional N with fish food?

steve