I'm refurbing an older pool and have come up against a problem that I'm unsure how to fix. The way the skimmers were built in this pool, the plastic of the skimmer bucket ends about 6 inches below the concrete pool deck (about the same level as the top of the skimmer entrance). The concrete had a (round) hole formed above the skimmer which supports the skimmer lid and essentially extends the height of the skimmer. The problem is that on both skimmers, a gap has formed between the skimmer bucket and the concrete above leaving a way for water to escape if it is above the level of the plastic skimmer bucket (due to waves or overfilling the pool). The gap is only about 1/8" on one side but is 1/2" to 1" on the other side and has significant space behind it due to erosion. I suspect it was like this for the previous owners for a while and they never did anything about it.
What is the proper way to fix this - fill the void with concrete then patch the gap with epoxy putty? Give up and have the pool filled in? Call a professional? Other solutions? Thanks!