Hello, Our free-form IGP pool has a spa to pool waterfall feature built of natural stones cemented in place to approximate the look of a river bed. The pool is aging, and the grouting/concrete used to install the rocks are developing hairline cracks that allow the water to flow behind and adjacent to the waterfall feature. We lose about 1" water per day beyond normal evaporation, and I'd like to seal the cracks. Several ideas came to mind (i.e. clear silicone, more grout or calking, drylok masonry sealer, etc.) but wondering if anyone has a pro solution/suggestion. Thanks.