Ray1214· Summer and Alyssa's Daddy
I use some of the epoxy putty sold in fish stores. It is easy to take apart but if you don't use it fast after letting the colors mix, it will cure some before you use it and won't stick worth beans. I personnaly like for large rocks, is to drill two holes, get those pvc threaded things (like screw tips on both sides) and twist them together. I use the epoxy (since coralline will grow on it) to cover up what is visible.