Freshwater Reverse Osmosis Membranes

Freshwater reverse osmosis membranes are thin-film composite (TFC) elements made for city water and well water with total dissolved solids (TDS) under about 2,000 ppm. They reduce hardness minerals, sodium, chloride, sulfate and other dissolved solids that cause scale, spotting and off tastes. These are low energy (low pressure) elements, designed to make their rated flow at about 150 psi, used in whole house, commercial and light industrial RO systems.

Choose by size and output

The element size is set by your system's pressure vessel. Rated production for each element (at 150 psi, 550 ppm feed water and 77°F):

• 2.5" x 14": 225 GPD
• 2.5" x 21": 400 GPD
• 2.5" x 40": 1,000 GPD
• 4" x 40" (4040): 2,500 GPD
• 8" x 40" (8040): 12,500 GPD

Actual output is lower with colder or saltier water. Each product page lists the test conditions, salt rejection and the systems the element is listed for.

Before you order

• Check your feed water. Freshwater elements need pre-filtered, dechlorinated water. If your TDS is above about 2,000 ppm, use a brackish water RO membrane instead.
• Replace as a set. Systems with several elements should get all new elements at the same time, about every 2 to 3 years depending on feed water, system setup and use.
• Under sink system? Those use 1.75" x 11.75" membranes rated 50 to 100 GPD, listed with all our RO membranes.

These elements are industry standard sizes and fit standard pressure vessels of the same size whatever the brand, including Crystal Quest systems.