That was kinda my idea, I plan on setting the sump up as a Algae Scrubber fuge and throw in a bunch of critters. This way the pump will ocasionaly kick a pod or two to the main tank. Also having plenty of rock in main tank will allow for a pod supply. My plan was to set up the tank and fuge and let it season/cycle before adding the SH's. This way if I have to leave them for a day or two, I could just dump a bunch of pods in the sump and let it auto feed.
My 110 Reef was a jungle of critters, at night there were clouds of pod swimming around, so it can be done. Another problem with throwing a Madarin in with the SH is the mandarin is a more efficient hunter, he can get into the cracks and creveses that the SH can't, there by limiting the pod colonies ability to maintain numbers.