Dirt coming down from cement coping

[attachment=0:14xkw1y5]downsized_0525122012.jpg[/attachment:14xkw1y5][attachment=0:14xkw1y5]downsized_0525122012.jpg[/attachment:14xkw1y5]Hello everyone,

Member here for a couple of years, sparkling pool due to BBB Method. Today while scrubbing waterline with a magic eraser noticed dirt coming out from under stamped concrete coping from top of pool. I kept wondering why I was seeing dirt on bottom of pool in shallow end. Wondering, should I caulk underneath the cement where cement meets fiberglass pool? If so, what kind of caulk shoud I use?


Yes, the white is the pool wall (bottom). The picture is sideways. The cement is gray on the right, stamped concrete deck, which has about an inch overhang all around the pool. Yes the gap is in center and is like that mainly around the whole pool. When water is splashed up onto the cement a lot of dirt comes out in that one area. I have seen a group of ants in that area must have been making a nest or whatever under the cement. They may still be under there but havent seen them lately congregated on the pool wall.


Mod Squad
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In The Industry
Apr 1, 2007
Sebring, Florida
I got it. I had a VERY similar situation. With the water level lowered so I could work, I got in the pool and first cleaned out that gap with a stiff brush, getting as much dirt out as possible. Then let it dry thoroughly....very important.

Next, simply force a bead of polyurethane caulk up into that crack with a little "overflow". I then wiped down the overflow with my finger to form a nice, clean rounded seal and then let it set up and filled the pool back.

It is important to use polyurethane and not acrylic. It's messy and won't clean up with water but will give you a nice flexible, fairly permanent seal.