hanging on the back isn't really an option for me. I've pretty much decided that I'm going to have to go with a canister. Or an undergravel, but I want sand, and I hate undergravels. It's probably a grudge thing, my old one shocked the crap out of me.
I'll check out the eheims and look into the renas more. I think the eheim is actually a little smaller, but neither is too large.
Is it naive of me to expect a 75 gal rated filtration system to effectively cover 70 gallons by itself? Or should I be looking for two canisters rated at that?
edit: btw, thanks a TON for your advice on shopping for one mHeinitz57!!!