Leaks - Learn how to stop leaks in their tracks | SpaDepot.com
Most blisters or surface cracks in the acrylic layer of the shell are only cosmetic, and rarely cause leaks. To repair surface cracks, drill a small hole (1/16" or less) on either end of the crack to prevent spreading. Thoroughly clean the surface around the crack, and apply either a Spa Bond patch, or, for larger cracks, Plast-Aid.