Depending on how much capacity we have designed, reverse osmosis membranes produce varying volumes of water each day. We provide membranes that can produce 24, 36, 50, and 75 gallons-or roughly 90, 135, 190, and 280 liters-of water each day. The temperature of the water, the distance from the unit to the holding tank, the quality of the incoming water, and the pressure of the incoming water will all have an impact on the output rate.