We are about to sign a contract with a fiberglass builder. Our last pool we had a saltwater system with a moss rock waterfall. This builder says we need to use RICO ROCK for the waterfall and stone. He says if we use natural rock it will flake off into the pool as the salt water will damage the rocks. We did not see this with our last pool but we were only there 3 years before moving. The rico rock coping is fine, but the waterfalls are not natural looking whatsoever. I need some advice, we want salt water but want natural looking rock. I am thinking of having the builder plumb for the waterfall and we will have a mason install later - natural stone.