are you doing a regulare rectangle 90?i just bought and setup a 90 gallon oceanic corner tank.i have a light fixture that i am trying to sell that would have worked perfect on a rectangle one,but this corner tank i'm gonna have to do something different with.i'm thinking about a lumenarc reflector with a 400 what 12,000k reflux bulb.i have one 175 over it now just to hopefully be enought to get by till i sell my fixture and buy whatever i decide to do for long term