I built a temp sump out of a large Tupperware container. I just got the elbows that I needed to complete the setup. I got an eshopps overflow box, which has two hoses that will drain into each of 100 micron prefilter bags. After that I have a pump pushing the water that drops into the sump through two inline filters: mechanical 5 micron filter and chemical. The clean water ends up in a small plastic waste basket. I push the hose to the bottom of that container, which I placed into the sump. I figure that I can dump a few gallons of Pond Matrix or Denitrate into that and then place a pump on top of the bio media to move the water back into the tank. I suppose I could get some kind of container to put the bio media in and just link that to the tank and I would need only 1 pump then. I don't know what to use for that yet.
All I know is that my fish are messy and prefiltering with a sump is going to make life a LOT better. I just wish I would have thought of my most recent idea before I bought the $100 mech filter... I'm thinking of putting a reducer bushing into a cap, making a custom gasket to place between it and the side of a pleated big blue filter. Then I'll run 1/2" pipe from that bushing, through the middle of the filter, to another bushing on the other end. The pipe will have holes in the middle for water to flow into it after passing through the pleats. Make two of those and connect with a 1/2" x 1/2" x 1" Tee and then connect that Tee to my pump. Awesomely cheap mech filter!! My only problem right now is that I want one of the bushings to connect via threads, so that the filters can be easily removed and replaced. All other parts would be solvent welded. I haven't put much thought into it, but it's Saturday morning here in the US, so maybe I'll get something done today.