Pick a site for your pool that’s sunny enough for aquatic plants to thrive but away from shrubs that might shed into the pool. To support fish and plants, the pool should be at least 11/2 to 2 feet deep. In some areas, pools of a specified depth must be fenced; consult local building authorities.
If you want to light the pool or install a submersible electric pump, locate the pool close to a source of electricity. The pump must be within 6 feet of an outdoor receptacle that is equipped with a ground fault interrupter. Check local electrical codes before running an outdoor circuit to the pool, or have an electrician do the job. Plastic-lined pools Garden and landscape supply stores sell flexible plastic pool liners and rigid fiberglass pools; both are easy to install. With a plastic liner you can design a pool in any shape you like. To determine the amount of liner needed, measure a rectangle whose length and width equal those of the pool; add twice the pool’s depth plus 11/2 feet to the rectangle’s length and width.
Outline the shape of the pool on the ground with a shovel blade. Dig a hole with sloping sides within the outline to the desired depth. Dig a shallow step along the hole’s perimeter in which to place edging material. Remove rocks, roots, and debris that could puncture the liner. Spread a finch layer of damp sand over the soil, and spread the liner. If you have a pump, place it in the pool and drape the cord over the side. Anchor the liner with bricks or stones. Fill the pool with water from a garden hose. As the liner settles against the sides of the pool, gradually remove the weights. Trim off excess lining, leaving a 6- to 8-inch lip. Conceal the lip with a rock or a masonry border.
Position a fiberglass pool on the site, and scribe its outline with a shovel blade. Dig a straight-sided hole about 6 inches wider than the outline and deep enough so that the rim of the pool will be 1 to 2 inches above the ground when installed. Remove debris from the hole, level the bottom, and spread an inch of sand over it.
If you have a pump and wish to conceal its cord, drill a hole in the pool below the waterline, using a 2-inch hole saw on a portable electric drill. Place the pump in the pool and run the cord through the hole. Plug the hole on both sides with plastic clay.
Lower the pool into the hole. As it fills with water from a garden hose, shovel in dirt around its sides up to the rim. Line the edge of the pool with rocks or masonry. Maintaining a garden pool Top off the pool as water evaporates. Periodically drain it with a siphon or pump and clean it. A submersible pump keeps the water from stagnating without disturbing its surface. To keep pool water fresh even without a pump, stock it with fish, snails, and aquatic plants.