You don't need a glass top but they are good for keeping the jumpers in the tank and the evaporation down, all that said I don't have tops on 3 of my 5 tanks...your tank is a bit too new to be worrying about livestock imo, but do you have any live rock in it to help it cycle? How big is your tank? Depends on what you stock it with as to how often you clean it as well....Welcome to the reefsite.....
