The Little Giant Pump company offers two different External Pond pumps for your backyard koi pond, waterfall, or water garden. These energy efficient External pond pumps are pre wired for 115 volt use but may be rewired for 230 volt use. The Little Giant External pump is intended only for out-of-pond pump use. These high volume external pumps are extremely quiet and consume less energy than the same power direct drive submersible pump.