Yep, dont get it. Trust me, like roka said, you want something that is 50-75GPD. If you had something that was 30 or 40GPD and you had a large tank do you know how long and boring it would be to filter your water for the tank? But then again, if you've only got like a 30G tank then i guess something like that wouldnt be all that bad, but you still want a 5 stage or more unit.
I just bought an ro
unit on tuesday from some place called cleandrink. Bought it for 120$ It was a 75GPD 5 stage unit. Good buy if you ask me. Also, it helps to get a unit that has cear filter casings so you can see when you need to change the filters.