You guys are probably going to laugh at me but about 8 months ago I used gorilla glue to stick multiple rocks together. I did it out side of the tank of course. I held the rocks together and kept the rocks wet by using a cup and pouring salt water over them for an hour. That’s how long it takes for the glue to be 99% cured. Remember that this glue foams up to cover gaps. Anyway, then I put them in a curing tank for 2 weeks. People are always wondering where I got such unique live rock boulders. Then I show them where the coralline has covered the glue seams. It's funny that no one else has tried this as you absolutely need a saw, hammer, or a gorilla to get them apart again. Let me know if any of you guys have tried it. -SoLiD