correct filtration for a 220gal tank

I'm having a hard time locating any AC500's on http://www.petsolutions.com/

Where would be the best place to find equipment of this type?

also, I don't feed my Oscar meat just big pellets and bloodworms.

NetMax wrote:

I think that two Magnum 350s and a UGF will not come close to meeting the
filtration requirements for these fish. These characters put out a lot
of solid waste. Where will it go? To quickly clog the Magnum's pleated
paper filter cartridge or to clog your gravel. This is a high
maintenance setup. I would put some AC500s in, with intakes low (crap
catchers), raise the intakes of the Magnums and install wide screens for
them (to maximize their water polishing capability), and consider
installing sponges on the powerheads and running RUGF. Then carefully
arrange your water flow to come down the back, loop and across the bottom
front of the tank to carry all detritus to the waiting powerfilter
intakes (which you can quickly empty/rinse as required).

jmo, hth