I was wondering if there would be any issue seeding a new tank with established rock from another tank. The only caveat being that the established rock has hair algae on it and will be put in a sump with no light. What would be the worse thing that could happen other than maybe getting some of the hair algae in the new tank which I can't for see happening because I have a sponge between the sump where the rock will be placed and the return pump to catch any loose ends?