Roy, The way to clean this type of decking is simple use no more than 1000psi while cleaning if you do you will blow the rock off the surface. Let the pool dry, then seal with a clear epoxy.When using epoxy you have to work fast since it has a 15 minute pot life, in other words it will harden and start to smoke and then it can't be used anymore.Also you need to use TSP or a multi-purpose cleaner,but do not use bleach.