A fish pond is a tranquil addition to any garden. Above ground ponds are quicker and less labour intensive to build than a traditional sunken fish pond. Wood makes a good material for constructing a pond above the ground because it is relatively lightweight and easy to handle and cut to size. Building a wooden frame fish pond combined with a PVC liner will result in a durable, waterproof structure that complements any garden.
Select the site where you will place the pond. Ideally, it should be a flat, smooth surface, preferably a concrete slab or wooden deck. The surface should be strong enough to support the weight of the water of the pond.
Cut the plywood sheet to size to form the base of the pond. The shape of the plywood base will determine the shape of the pond.
Cut the 10 cm by 10 cm (4 by 4 inch) timber posts to size and lay the four sides on the plywood base to form a rectangular or square frame. Drill the corners of the posts at a diagonal angle to accommodate the 25 cm (10 inch) bolts. Join the four corners of the frame by sliding the bolts through the drilled holes at each corner. Tighten the nuts securely.
Tack the bolted frame onto the plywood base with nails. The first layer of the wood pond is now complete. Drill three evenly-spaced holes at the top of each side of the frame, 5 cm (2 inches) deep, to accommodate the 1.2 cm (1/2 inch) wood dowels. Cut the dowels to 10 cm (4 inches) in length, place wood glue on the ends and tap the glued ends into the drilled holes on the frame. The dowels should protrude 5 cm (2 inches) above the top surface of the frame.
Build the next framed layer by bolting another four posts together as before. Measure and drill 5 cm (2 inch) holes at the bottom of the second frame to accommodate the dowels protruding from the first layer. Place wood glue into the holes and tap the second frame layer down firmly onto the first frame until they meet flush and are secure. Repeat this process, layer-by-layer, joining each bolted layer to the previous layer with glued dowels until you reach the desired height of the pond.
Place the PVC liner inside the wooden structure and smooth it out so that it fits snugly against the walls of the wood structure with as few creases as possible. Tack the liner onto the top ledge of the frame and neatly trim the overhanging edges. Cut the 10 by 2.5 cm (4 by 1 inch) planks to form a frame and nail them onto the top ledge of the structure to finish the pond. Fill the wood pond with water.
Use only pressure treated wood, which is more durable and weather resistant. Make sure the PVC liner is properly sized by taking the height of the pond walls into account. Fill and drain the pond twice before stocking it with fish to ensure it is clean and safe.