Vlondi,
I have 3 lights setup in my canopy. I use the HQI pendant in the middle since its over the glass tank support. The bulbs on each side of it are single ended bulbs. I use eggcrate to keep fish from jumping out of the tank. I noticed that if you keep your glass on it makes the tank really warm plus it drowns out the "wavy water" looking shadows that the MH bulbs make in the tank (make sense?). If I had it all to do again I may have gone with 3 HQI pendants just because they are so easy to hang and it forces the light down into the tank unlike the reflectors.