I just bought a 125g for my two tiger oscars and am having trouble coming up with a sufficient filtration system. I got a Emperor 400 Bio-Wheel first so I can go ahead and start the cycling process. I was eventually going to get another one before I put my fish in. The 400 says it is up to 90 gallons (that's why I was going to use two), but do I need to look at bigger filters? And if so, which ones? Also, my LFS is selling the 400's for $80, but on drfostersmith I can get one for $48. Am I missing something here, or is it really that much cheaper online? Also, any thoughts on the under-gravel filters (as a combination with the power filters) benefits? downfalls? Thanks!
