Lighting: T5 vs Metal Halide???

[TheMikey]

That makes a lot of sense. I was doing some PAR readings on my tank last night and was getting about 680 PAR on the bottom of my 15G (about 16" from bottom of light to bottom of tank) with a 4x24W T5 setup. I'm using 1 x 15K, 2 x 22K (all aquascience), and a stock Actinic. I thought that was WAY too high.

Regardless, though, all I really care about is if my SPS has nice polyp extention (and they do!) and good colour.