I'd like some expert advice on how to repair (hopefully myself) the cracks that have developed in the spa / spill over of my inground pool. The pool is ~7 years old, we are the 2nd owners, pool was here when we moved in 3 years ago. It is a salt water pool with infloor jets. (bummer, but it's in). The flat rocks that form the spillover have become loose from the supporting wall and pass water beneath them instead of over the top as designed. I think that the wall structure has become saturated and has now swollen which has cracked the Pebble-Tec finish inside the hot tub. When the pumps are off at night the water line is just below the bottom of the flat spill over rocks, starts at the top but leaks into the pool until it finds the low spot leak.
My thoughts for a repair, (I'm a General Contractor and experienced in tile and concrete work)
Drain hot tub, remove top flat spill over stones, remove any loose or unstable wall structure underneath. Let dry for a few days, (pool will be off) wire brush off any deposits on the (once) underwater cracks in the spa, fill small cracks with an epoxy. Rebuild / repair any structure beneath the spillover area, seal top of wall with a "redguard" type compound, and reset flat spill over stones with thinset. Then regrout.
My questions are:
1: Do I / should I, use a grinder and channel out a small groove on the spa cracks? <1/16 inch now
2: What epoxy / Pebble Tec repair material should I use for the crack repair?
3: Is "Redguard" appropriate for pool chemical use? or should I use a different waterproofing system/ material? Drylok / Thoroseal? Does it matter if the top of the wall is waterproofed before the stone is set?
4: Is ceramic tile "Thinset" the correct material to reset the flat stones?
5: What is the correct type of grout to fill the spaces between the stones? Currently it is a very coarse grout.
Thank you all for your help once again.