Ponds are a great way to landscape your property because they provide diversity to a garden or lawn setting. They can provide entertainment if filled with fish or they can be a calm place to sit and enjoy the setting you've created.
Ponds need to be waterproofed and lined before they can be filled with water, fish and plant life. Waterproofing will require that you seal your concrete pond with a sealant, add a liner bottom and then a liner to ensure that the pond is fully waterproof. There are vast options available for these different product categories. Often one company will produce a full line of waterproofing materials.
There are many sealants on the market made for various jobs. When choosing your choose one specifically meant for concrete. One company, Duram makes a pond sealant called "Durapond" that is clear in colour to avoid disrupting the visual appearance of the pond area and non-toxic so that it doesn't affect life in the pond. It is a polyurethane waterproofing paint.
Another pond sealant offered by Pond Armor and called Pond shield is an epoxy based sealant that is also non-toxic to fish and plants in the pond. Pond Shield comes in five different colours including beige and white.
If you have any deep holes or gouges in your pond you can fill them in before you seal with a product like Liquid Rubber Base (LBR), made by Sani-Tred. LBR takes on the shape of any gaps that it fills, making sure that there aren't any left over open areas in your crack or hole.
Pond Underlay Liner
If you choose you can add an underlay liner over your sealant, to add an extra layer of waterproofing assurance. The underlay liner helps the liner to resist punctures from any break down of your pond foundation. Underlay liners are available from a number of retailers who sell pond liners and other pond supplies.
Pond Liners are usually made from durable, thick PVC material made to withstand the UV rays of the sun. They come in black, blue or grey and are available in a wide variety of sizes to accommodate different sized ponds but can be customised by cutting to fit into oddly shaped ponds. Some of them come with a year warranty, but typically have to be replaced after two or three years of direct sunlight.