I suggest not going for preformed, only because the pond liner gives so many more options regarding shapes and sizes and I am sure it might be a bit cheaper.
I think the pond liner is the most expensive item you would be paying for. If this is a DIY project, you can save on labor cost, which is normally outrageous in cost.
1 Doberman Mix: Emmy, 2 DSH Cats: Rowan & Jacob, 1 Bearded Dragon: Rainier (aka Mista Lizad Man), 1 Eastern Box Turtle: Greta, Two 5g tanks: Alchemy (Halfmoon) and Custard (Yellow VT)
Last edited by ThePearlFish; 11-22-2012 at 02:26 PM.