and of course I have many questions on the topic! I was at Home Depot (kind of like crack to me) the other day in the lighting section (getting ballast, of course) and I ran across their MH selection. They have ballast for all the various sizes (175, 250, 400watt) for cheap (relativiley) and lights, whoah - they have phillips 175watt MH's for $28. Can I use either of these products on my tank? I pretty much figure the light's are a no-go, but what about the ballast? There isn't anything special about aquaria ballast, correct?