My cat just came home from the vet. It was shampoo'ed and flea dipped. The smell of the flea dip was very strong. I put him down and did something else. When I looked at the cat he was all nice and clean sitting in a puddle of salt water on the kitchen floor. Little thing jumped into the sump to wash off the flea dip. I wrote the entire sps reef off as dead. AFter 2 days and no ill effects, I figured I better run some carbon on there and get it out and do a water change. Didn't hurt anything in the reef, fish, corals or inverts. If the sump is setup correctly, any dust or hair gets caught in the fibre mat or sock filter and does not return to the tank.