Water falls from a reflecting pool, flows through a special sand-like media, and creates beautiful patterns before being filtered and pumped into the reflecting pool again. Left on its own, the water will produce river deltas, a shifting river bed, and even oxbows. When visitors dig in, they create dams, jetties and other civil engineering projects. We have chosen a mix of recycled plastics in five different grits for the sand-like media. Each grit is a slightly different shade and settles at a slightly different water velocity, producing beautiful and instructive patterns. Not only does the plastic grit produce patterns on a smaller scale than sand or gravel, but it harbors less bacteria because it is smooth on a microscopic level. The circulating water passes through an ultraviolet filter to kill germs and is automatically replaced with fresh water as needed.