There is a small crack in the overhead water tank, about 6 inches by 1 inch. The tank is made up of fiber glass. Is there any chemical that can be used for filling the crack?
When I worked in a fiberglass piping company we used a fiberglass resin mixture that was thickened with a product called aeroseal. This made the resin extremely thick which allowed us to fill spaces between two fiberglass pipes. The mixture was then sanded and fiberglassed with resin and glass both inside and out.