Tom, another question I started to ask myself, and we already talke a bit about it in previous thread, but I wanted to break it out to a new thread.

I understand that marine macroalgae seems to have a slower uptake rate of nitrogen then freshwater plants. Therefore, the KNO3 doses should be lower.

But on the other hand I observe quite a lot of small bubbles raising from my DSB to the water surface. And I see a lot of bubbleformation in the sandlayer close to the tank's sides. As I understand it must be denitrification going on there. It means that my substrate - and probable some live rocks - "consume" some of the dosed KNO3.

So maybe - just a speculation - we could dose quite more KNO3 to compensate for denitrification? Is it safe for fish and invertebrates (corals aside) to dose say about 20 ppm NO3 in a macroalgea-only-tank?? Why should the NO3-dosing should be lower?

Any thoughts?