This tank will be the foundation for my AP system for this spring/summer. I've built a box, 4' wide, 8'long and 2' high - which translates into about 475 gallons of water. I'll put up pics soon, but first I've got a few questions for anyone who has ever used PVC pond liner. How long should I have the water in the pond liner before I put in the fish? I've got some Mossies that need a new home .... a much bigger home. I've got the biofilter already cycled, heater and air pumps are all ready, the water will be charged up with about 70 gallons of used fish water plus about 400 gallons of fresh water, I should have the pond liner in place tomorrow morning and then I'll start filling the tank ..... the only thing I have to determine is how long it takes to season the liner so the fumes of the liner won't affect the fish! Any Ideas?