A pool side waterfall can be best built with prefabricated material. In this case real stones and rocks will not have to be used. The size of the waterfall should be in proportion to the size of the swimming poll. Also care should be taken to keep the backside of the waterfall away from sight. Depending on the size of the waterfall an appropriate capacity water pump will have to be decided on. Generally nothing bigger than a two or a five horse power pump is necessary. Waterfalls connected to the pool are considered far more beautiful and the water of the pool itself can be used to circle round the waterfall. The water can be made to come down in more than one direction coming gently in a step pattern at one end and tumbling into the pool and forming a curtain of water at another.