10 catalysts While purchasing water fountains for your outdoor garden , the question comes why solar water garden fountains ? Well, Solar fountains are a one-time investment only. These are charged by solar energy and will keep moving water the whole day without any further hassle. During day time they will work best, and waterfalls for home if there is a need for water flow in the evening time, the solar fountains must be accomplished with batteries for energy storage during nighttime.