I just setup a 90 gallon tank, up from my 20 gallon planted. I bought the tank used which also came with two PC light fixtures. What plants am I limited to with 220w of PC (10000k) lighting over the 90 gallon?
The plants that wouldn't do well with that much light are very few. You can do red plants with no problem. I have A. reinickii growing bright red with 2.4 watts per gallon, and my other red/purple plants do fine.