At the moment in my 4x 4 flowering room I have 5 600watt HPS. It probably is overkill but the plants love it. Real light saturation. My yields will be up, the strength will be up and the plants love it.

Once plants reach the stage where they can absorb so more light their cells evolve to ones that can. All plants do this apparently so perhaps the same can be applied to the magic green?

And what is overkill anyway?
Surely more light equals ore bud and more healthy plants. My temp is high, true but only in the mid eighties and the humidity is really low arond 20-30%. I have no mites, insects, mould, fungus or any bad leaves.

I have a pile of thirty HPS just sat here so it seems a shame to not use them. Ok I am now hampered by how much electricity I can atually put through the circuits in my house. With those 5 x 600 watt HPS i also have another 6 HPS 600watt downstairs with 1500 LED power at horizontal level. 100+ lowryders love it!