[Avalon]

Originally Posted by ishar

I have a question though. You mention 10ppm as being a decent benchmark for K levels. Does that mean you should dose 10ppm per day or just get it to 10ppm after a water change say, and then dose smaller amounts to cover the uptake as the week progresses?

The latter. Many say you don't need additional K when dosing dry ferts since they all have K, but raising the initial amount seems to help with a few plants, namely Hygrophila sp. From there, the dosing of N & P ferts should be enough. I would re-dose K at about once per week (if no water changes), more under very high light conditions or a heavily planted tank with a high growth rate.