Flexible pond liners can be used to create ponds of any shape and size. They offer reasonable cost with ease of installation. First you need to dig the hole for the pond, install the underlayment, lay the liner in the hole, fill the pond with water, cut the liner to size and then weigh down the exposed edges of the liner with large rocks or other materials to keep it in place. Flexible pond liners come in stock sizes ranging from about 5 x 5 to 30 x 50 feet.You can usually, depending on the manufacturer, get custom sizes, which would be priced by the square foot. You can also join the edges of the sheets with a seam sealer to make a pond of virtually any size. Keeping the pond level in all areas is important so that the base can not be seen when it is filled with water.
Because flexible liners are susceptible to punctures from rocks, gravel, broken tree roots, or other sharp objects, installation would require putting a layer of sand, carpet padding, or similar cushioning material in the excavation before laying the liner. Research this because if you are planning to build a large pond or have steep sidewalls you might find problems when using sand and newspaper or cushioning materials tend to deteriorate over time.
Ridgid or semi-ridgid pond shells are easy to install yourself. These shells come in a variety of sizes, shapes and depths. Although they are generally more expensive then pond liners, they are also more durable and puncture-proof. Shells can last from 5 to 50 years, depending on their material, thickness, quality and instalation canditions. Some shells have integrated premolded waterfall lips; seperate premolded waterfall courses are also available. Many preformed shells have shelves or ledges around the edges below the water line for placing shallow-water plants in submersible containers. You should carefully disguise the edges of the shell with rocks or other materials, so the pool will look natural. Pond depth is also another important factor when choosing the type of pond you want.
