Iwaki MD70RLT Pressure Pump Iwaki MD70RLT Pressure Pump To return water to the main tank I use the Iwaki pump shown to the left. There are American made and Japanese made versions of these pumps. A pump with "MD" shows it is Japanese made, a "WMD" shows it is American made. Unfortunately the American made pumps are of a much poorer quality than the Japanese pumps. The Japanese pumps are smaller, quiter, and run cooler. I wish it wasn't so, I don't like to bash products made here in USA. Iwaki pumps also come in circulation versions and pressure versions. "LT" are for circulation, "RLT" are for pressure applications. Even though I'm using the pump for circulation I paid a little more money to get the pressure version of it. This mainly means that if I have a flow valve after the pump, I can reduce the flow, which adds backpressure to the pump. A pressure version should have no problems, a circulation pump may have problems with overheating, or impeller breaking, or other mishap. Input: 1 inch MPT Output: 1 inch MPT Power: 2.8amps, 60hz, 110 volts. Moves 1,500 Gallons per Hour at 4 foot head presure. I currently use this pump as my primary return pump which feeds water into two ¾ inch SeaSwirl units.