I haven't ever used it, but have seen concrete stain on television. I don't know that it's a permanent solution in a pool area with chemicals and such, but it might be worth asking a professional. Don't know much about in ground pools, but if you're considering adding stone pavers and can't find them, you might check into stamped and colored concrete. Neither the stain nor the stamped concrete will be as pretty as natural stone, but either one might work if the goal is to simply break up the gray of the current concrete.

All things considered, it's a pretty good problem to have from where I sit socked in by last week's northeast blizzard. Enjoy your warm Mississippi winter!