I am thinking of upgrading to MH but don't know a whole lot about them. Can you run a DE bulb off of any ballast or does it have to be a ballast made of a DE bulb? What would be the best brand of electronic ballast? Is the any advantages to going with a DE bulb compared to a SE bulb? Are the any advantages to going with an electronic ballast vs magnetic? Would a 400W system be too much for a 75 gallon? As you can tell I don't know a whole lot about Metal Halides so any advise would help out a lot.