im keeping some sps corals, namely a green slimer, a small frag of a baby blue acro, and two montipora caps, a brown and an elec. orange one, and the montis seem to be doing the best and growing the most, the tru acros have good polyp extension but not a lot of growth.
this is under 130 watts of pc light in a 20 gal, whis is like 6.7wpg, however they will all be going in my 65 soon with 2X 250w Mh, and 2 2ft vhos and will be under 10 wpg total!
good luck
jon