Beneficial relationship between sponges and corals (article attached)

http://ift.tt/1VN6YWa

I stumbled across this and thought it was really interesting, im thinking about getting into sponge keeping, maybe building a cryptic tank as part of my sump made with a small black acrylic trough that has decent flow and no light.

The interesting part to me is that the shed sponge matter can feed other tank inhabitants while also cleaning the water column.