Since I don't currently have anything to replace them with, I left them both in..I should be making a trip to the LFS
next week so I plan on swapping them out then. In the meantime, everything's still running perfectly with the small sponge gone. One other question - what's the proper way to siphon the tank (I have the Python)? There is a lot of debris in the live rock, but it seems impossible to siphon it from there without disturbing the rock. Thanks again.