I need some advice. My pool is an inground vinyl liner with cantilevered concrete decking. We just had it installed in January. I have noticed while swimming recently that there are a few gaps between the top of the fiberglass steps and the pool decking. This appears to just be an area where the concrete didn't settle all the way out to the bottom of the styrofoam cantilever forms. It doesn't appear to present any problem it just catches my eye every time I get in the pool and I don't want to take a chance on water getting back behind the steps over time if I can help it.
My question is what should I use to fill in this gap? Polyurethane caulk or is there something better to use? We are going to have a coating similar to Kool Deck applied in a few weeks but I would like to have this done before then so it can be painted over to match the coating. Any suggestions?