OK guys. I know you're probably tired of the undergravel filter thing, however, I'm confused. I had decided to get one for the 25 gallon tank I am getting on Saturday (yeah, finally!!). What I want to know is, do you buy the filter plates seperate from the power source (?? pump??) ? (really hope that makes sense). The undergravel filters that I have looked at, look like they have the plates and tubes running up. Do I have to buy the canisters seperately, or how exactly does this work? I am really sorry for this, but I just want to know what I need to look for. (Being a newbie really sucks!) Thanks for the help.