rocks coming unglued

If your tub is fiberglass, then any slower cure two part epoxy will work fine. The factory adhesive may have been a polyester resin similar to the tub resin. Some of these are fairly good adhesives, though not in the same class as the epoxies. The rocks themselves may have contributed to the problem if they were something like soapstone or a talc conataining rock. If the rocks look dubious, try some better ones from your local garden center or similar outlet. Good luck.

Joe

Try this:

Did you have a point with that insult or do you just like to be obnoxious?

Perhaps it is obvious to you what should be done, but not to me. Seems to me that epoxy may not be strong enough to hold them up and I dont want them falling off on someones head and drowning them. It looks like they were cemented in but I cant imagine slapping a fresh layer of cement under the 10lb rock and expecting it to hold. I do have some epoxy in the garage that I can try but was hoping that someone might have recommendation as to the right stuff to use before I go for it. One of the two rocks is on the side so the weight of the stone will tend it to be pulling away from the epoxy.