Waterline Tile Replacement

[dave orso]

I have an old IG gunite pool. We were going to have the entire pool renovated (replastered, new tile, coping and deck) however it was nearly impossible to find a contractor. Finally decided to replace the waterline tile, coping and deck myself and leave the plaster for another time.

Well, I removed the old tile by cutting underneath it with a diamond blade saw and then chipped the old tile out. There are several spots that the plaster came off immediately below the tile line (up to 10 places that are
1/2" x 2").

Once the tile was removed, I replaced it with new tile using a thinset. Nearly all of the tile is flush with the old plaster. Some (15 linear feet) is set out from the plaster wall nearly the depth of the tile.

Need a recommendation on whether I should plaster up to the bottom of the tile around the entire pool and how I would actually accomplish this without it looking odd. I am assuming the new plaster will be bright white and the current plaster is so old and discolored it will not be even close in color.

I thought about applying tape a couple inches under the tile line and then applying the plaster.

Would applying grout under the tile as well as between the tile joints provide a watertight seal to the old plaster, and is this a better option than applying plaster?

Another thought was to saw cut another line around the pool perimeter approx 1 or 2 inches under the tile and chip out the existing plaster and replace it with new plaster.

Would appreciate your advice and feedback.