That 32 deep is going to be rough to light. I'd recommend something like 4-6 Xr15's/kessils/hydras. If you supplment them with T5's though, you'd be set. Could do like 3 Xr15/Xr30/Kessil/Hydras with a 4 bulb T5 Aquatic Life 48-60" fixture and you'd be set.