a little fishfood will do it, too. THere's a 'setting up' sticky ^^ that may give you some general help. Water chemistry is everything in the marine hobby, and understanding the way it works will keep you from troubles. Basically the bacteria need to eat in order to reproduce, and you'll be nurturing a variety of them into a whole lot of them. As long as that happens, and as long as you go slow at starting, your bioload will never overpower your processing power.