Spawning tank for petricola?

[toddnbecka]

I currently have 9 that appear to be spawning size, a couple of the females are looking gravid. (Big bellies, not from recent feeding activity) What size tank, and what kind of setup, would be best for this group? I have been considering setting up either a 30 long or a 40 breeder tank for the project, with a piece of eggcrate raised about 1/2" off the bottom instead of the bowl of marbles to catch the eggs, or possibly a piece of eggcrate over an empty bowl. Would this type of arrangement make the air-driven lift tube/net breeder idea work? Will petricola eat eggs in a net breeder, the way some cichlids eat fry out of them? Would a divider in the tank be a better idea, with the outflow/eggs being on the other side of the spawning setup?
Do they spawn over a period of several days, or do they finish in a few hours?
Any help from successful experiences would be greatly appreciated. I've wanted to spawn Synodontis in an aquarium for years, and have spent the last one waiting for the fish to grow big enough to start.