Im going to get my 20 gallon setup tomorrow and i was wondering which filter to buy the aquaclear 50 or 70 or the marineland biowheel 100 or 150? i wont be using a pump and air stones. can i have pros and cons of each? 
word;, they are cheap and effective, although i hear the bio wheel provides better bio filtration. i am a big fan of my AC'cGet the AC, everyone seems to love them.