I have 2 Bio-wheel filter and 1 Emperor Biowheel filter. I hate my Bio-Wheel 330, and 125, but i LOVE my emperor. I am constantly having problems with my bio-wheels. The emperor holds more media and it is alot quieter. If i get a biowheel filter i stronglt reccomend the Emperor 280/400 Instead of the Bio-wheel Mini, 125, 170, and 330..