Preformed ponds are a great solution for first-time pond owners, as they are often much easier to install and maintain than ponds made with poured concrete or a plastic liner. Rigid pond moulds can also be dug out and relocated in the event of a move. Installing your own preformed pond doesn't have to be a hassle, either; with some basic preparations and a little digging, you can have a beautiful pond settled and ready to enjoy in no time at all. (The following steps are to install a basic two-level preformed pond, but they can be adjusted to fit any shape and size.)
Trace the outline of the pond shell on the ground where you plan to place it. Spray paint, chalk dust or even dirt works well for the purpose. Make the outline about three inches wider than the pond's overall dimensions.
Dig out the depth of the pond, adding two inches. Mimic the outlines of shelves and steps as much as possible while you work (for simple two-step designs, you can dig out the first step and then place the shell over the hole to trace the outline of the base). Reserve the soil you dig up.
Place the pond shell into the hole to check the fit, making any necessary adjustments. At this point the pond does not need to fit perfectly, but it should be roughly level and resting about two inches below ground level. Remove the shell from the hole again.
Add a 2- to 3-inch layer of sand to the bottom of the hole and the tops of the shelves, levelling as you go.
Replace the preformed pond shell, and check again that it is level. A long board with a level taped to it makes an excellent tool for this.
Begin to fill the pond with water, slowly backfilling dirt outside the shell as you go. Work so that the dirt reaches the outside lip as the water reaches the maximum fill point inside. Check your level as you go.
Shovel remaining dirt around the pond lip, packing firmly. Make sure that the dirt slopes slightly away from the lip of the pond to prevent water from carrying earth and debris into the pond if it rains.
Hook up any pumps, heaters, and filters. You are ready to begin landscaping.
Large flagstones make great pond surrounds, as they can help to disguise and soften the edge of the liner for a more natural look. Potted plants and larger stones can be used to help anchor these in place and add stability. Make sure to use a commercial chemical remover before adding fish to your pond.