i agree. i have a 300g with 2 fx5's 1 empo 400 and 1 empo 280. im slightly overfiltered because of my stingrays and large arowana. but i think for most 2 fx5's will do the trick for most people.
I agree if you don't want to spend the time to design a reliable sump (can be time consuming the first time around and a bit of trial and error) Id say two FX5's if you shop Ebay they can be had for around 230 each maybe cheaper.
