Ok...What I was thinking is. As you can see in the third pic 1 1/2 pvc
fits it perfectly. Water would come in the at the top on the side of the pipe, then get sucked back up the pipe.Travel through all three canisters and return back to the tank.
Maybe I'm missing something, but I didn't think I would have to change much at all. The tubes in the pic are empty as of right now.
If nothing else I was hoping to use it to at least seed some media, as I plan on having 3 large tanks running.