Truck bed liner in fountain/pond

Hoping this will help someone... I'd been having trouble w leaks in my concrete fountain/fish pond for 20 years and tried multiple solutions. Recently put in "rustoleum truck bed professional grade kit" and it works like a champ. Took about 3 months of rainwater and off-gassing (?) to support fish again. I needed more material then the instructions said for thicker coverage but works great and was easy to paint and roll in.