Hi, I'm building a koi pond 10 x 13 by 7' deep with block walls and will probably go with fiberglass sides and bottom. Unless I can find someone good in Minnesota that can apply polyuria coating correctly and have no leaks after it's done. My question is what do I do with the bottom if I fiberglass it? Do I cement it or is there another way to be able to apply fiberglass? I will have a bottom drain.
Thanks for your replies.