I'm doing the same thing. I just got my 240 long yesterday, but I've had the filters for it for about a month running on various tanks. I'm using a Fluval FX5 with the foam blocks, biomax, pot scrubbies, and some filter floss, a Magnum 350 filled with carbon and biomax, and 2 emperor 400's with carbon and matrix. Hopefully it will be ready quickly. Tell me how yours works out!