Do you make fish ponds out of them Texas? I've heard of using a truck bed liner, gues those irrigation tanks would work too as long s all the chemicals were washed out of them and they had awhile to "cure" with pond water. Course you can have frog ponds with plants and no fish, I have a 100 gallon "frog" pond...no frogs though, lol!! They like the big one better. So what will you do with the tanks?