sealing sandstone

We have moved into a home with a backyard of Arizona sand (http://maplered.com) Stone (http://g603.net) .  It includes a salt water pool.  There are a few Stone (http://g603.net) s by the pool deck that are always peeling.  My concern is, if I apply a sealer it will only make the peeling in deeper layers.  Any suggestions on Product or application?  Cost is a factor.  There is over 

1500 sq ft of flagStone (http://g603.net) .  Thank you, Diane, Arizona