Yeah, I always move stuff around or add a new rock when I add a new fish.

If they are still going at it tonight when I turn the lights back on, I'm going to implement the egg crate idea. I have an unused piece that I need to cut. I'm almost certain I will not be able to get it to fit tight enough though but we'll see.

Thanks for the replies...I'll post an update later. The things we do for our tangs...LOL!