Locate your pond away from large trees to avoid excessive shade. In addition, digging into tree roots may damage the tree as well as your back. Decaying vegetation in the water depletes oxygen, so skim out any leaves that do blow in. Now that you've found just the right spot, experiment with the pond's size and shape by laying out a hose to represent the pond's edge. Your pond need not be deeper than 1 to 2 feet, unless you're planning to stock fish.
Minnows are excellent mosquito larva eaters.
Goldfish are bottom feeders. To prevent puncture, put a protective underlayment between the ground and your liner. As the newspaper slowly decays, it actually forms a watertight substance called gley. Concrete contains chemicals toxic to aquatic life. Scrub concrete ponds with muriatic acid and rinse thoroughly.