How to Build a Pond Above the Ground That Creates Its Own Oxygen Like a Pond in the Ground?

Pick a spot for your above-ground pond. The best location should get a mixture of sun and shade. It should also be located near an electrical outlet, which will provide power for a pump and/or filter. This will also give you an idea of how much area you have to work with for your pond. Take rough measurements with a tape measure to determine the possible pond area.

Choose a construction method for your pond. For above-ground ponds, there are a couple of choices you can go with: either use an existing object to hold the pond, such as a gardening container or water barrel, or build your own to size. You will also need to determine if you are going to winter fish in the pond. In this case, you will need a pond with a depth of at least 3 feet in order to keep the fish safe from freezing.

Prepare the pond. Level the ground on which you will be installing the pond to provide an even surface.

If using an existing container, cover the inside with pond liner. Trim this roughly to size. Using adhesive caulk in a caulk gun, apply caulk to the sides and bottom of the container. Press the liner into place against the caulk. Trim off the excess liner around the edges of the container with a utility knife.

When building your own container, take the measurements of the area and use the dimensions to cut the lumber sides of the container using a power or hand saw. Nail the sides together. Lay out the liner as you did with the already-constructed container and the adhesive caulk.

Pick a number of oxygenating plants to live in your pond. These plants produce oxygen in the water for use by fish and other wildlife. Some good examples are Hornwort (Ceratophyllum demersum) and Water Milfoil (Myriophyllum demersum). However, the best oxygenating plants for your climate are those that are native to your region. These types of plants should not take up more than 70 percent of the available pond space.

Measure the square footage of the surface area of the pond to determine the number of fish it can safely support. You will need to have approximately 24 square inches of surface area per fish. For example, a 3-foot-by-5-foot pond (36 inches by 60 inches), will support up to 90 fish. However, because koi and other fish can grow as they age, you should only use a third of that number. So a safe maximum in this case would be 30 fish.

Install a filter and pump. The pump helps to push the pond water through the filter. You can also attach a water feature, such as a fountain, to the pump, which will help oxygenate the water. The easiest of these types to install are the submerged pump and filters. In some setups, the pump fits inside the filter, which makes for a compact and easy-to-maintain setup.

Fill the pond with water from your house tap. Before fish and plants are put in, the water should be treated with a dechlorinator. Follow the instructions on the dechlorinator during application.

Place the oxygenating plants, in their pots, on the bottom of the pond. Keeping the plants in their pots allows for easier pond cleaning in the future. If you purchased the plants separately without pots, plant them in pots with the roots covered by aquatic potting soil. Place rocks on the top to weigh down the soil and the pot.

Add any fish to the pond. Lower the fish in their bags, complete with the water purchased from the fish store. Allow the fish, water and bag to float in the pond for approximately an hour. Open the bag and release the fish. This allows them to become acclimated to the pond temperature.