well i did try that to my fishtank and i found for sum reason that the outside rocks as well as ocean sea shells produce algee alot quciker…im sure they look really nice and its safe to use them maybe boil them in hot water to disinfect them from the outside pesticides .. honestly i wouldnt do it though i have realized that…
fish and fish care are very very sensitive they build there own enivorment in the water they live.. but if u are cleaning the fishtank and adding new water and stuff than go ahead but i wouldnt otherwise…