Powerful magnet drive pumps are made to run continuously, without seals to wear out and are highly energy efficient, using half the energy of a direct drive pump. The completely submersible pumps are filled with epoxy, not oil, so they cannot leak oil into the pond. Suitable for statuary, fountains, ponds and/or fresh and saltwater aquariums. UL listed to U.S. and Canadian safety standards and approved for indoor or outdoor use. Model TT Mini Pump Suitable for table top fountains Models 3.7 & 5.1 Suitable for medium garden fountains, piped statuary and ponds Model 7.5 Suitable for medium to large garden fountains, piped statuary and ponds.