Little update. I called the company that makes the liner and was told they dont use anus chemicals.
I got a stock pond from work for free because it has a crack. I took the liner I got and put part of it in the pond and filled it up. Waited 24 hours and then put 25 goldfish in, I remember reading if they die then its not safe.
12 hours latter. They are still alive, going to waiy another day or 2 before I call it safe.