what do you guys think about a pool liner for a pond liner ? i have a friend that is giving me a pool liner for a above ground pool that 20ft circle and 5 feet deep. no leaks or anything shes just buying a new one. i live in florida so the coldest it gets here is in the teens like 3 times a year ,so what should i stock ?i really dont want to heat it but i guess i could put it in the sump that im going to build out of 4 -30 gallon drums .