The Aquadyne Retrofit Bottom Drain is a stable and rugged over the liner bottom drain for those who do not want to install a drain through a liner, or for pre-constructed ponds that do not have a bottom drain. This drain is especially useful for pond and aquatic environments that have pre-existing liner, concrete, or any other situation that would not allow underground plumbing to be installed. Simply fill the ballast area of the drain with small stone, sand, or other heavy inert material. Then attach a suction hose or rigid plumbing to the side port of the drain and attach to the pump suction line. Place the drain in the center or the deepest part of the pond so that the pump can easily suck up suspended solids and debris from the bottom of the pond. During the winter months, the drain can be easily moved to a more shallow part of the pond leaving the warmer water in the lower parts of the pond undisturbed where the fish collect in colder temperatures.