from my understanding, with powercompacts, NO. I have 440 watts of VHO on a standard 55 gal. and they tell me I can't do it. I ordered a single 175w MH kit and its coming in Friday, can't wait!!
I think a Squamosa, Durasa, or Gigas will work just fine under that lighting down on the sand bed. Possibly a Maxima if you put it high up directly under a 10,000K. I don't believe a Crocea would work.
Remember that small ones rely mostly on Phyto and need to be fed (not directly though).
Guy
I just bought one a few days ago. I have a jbj power compact. 360watts 2 10000, and 2 att blues. The guy I bought from said I could keep it as long as I kept it close to the top and I had good Ca in the water. I really wanted the blue one. This guy had awsome prices. The little blue from the red sea was $85 and the one I got is $35 mine is purple. I lost a little color from his tank to mine. Not sure why yet. He did not have a lot of light. here is a pic.
Ohh never mind I just noticed That If I look at it from the top of the tank It was realy colorful. I just moved it to tilt it a little more. Hopefuly that will work better.
When you look at this. Just think of the lighter color in it being almost an electeric purple. That is how it looks looking strait down on it in my tank.
worm, who told you you cant with 440 watts of light on your tank? what kinda bulbs do you have 10K and actinic? I woudl think this is more than enought to keep a derasa and squamosa, and probably a maxima. ive kept clams under pc lighting for about 4 years now. i have a blue maxima in my 20 gallon under 130 watts of pc llighting!
good luck
jon