Hydron BW-4040 Reverse Osmosis Membrane – 4" x 40", 2400 GPD | High Performance for Commercial, Industrial, Agricultural, Whole House | Compatible with AG4040FF, AG4040TF, TW30-4040, RE4040-BE

I bought this in March 2023 and it has met expectations. There was a noticeable improvement as soon as I replaced the old one with this new one. Since this purchase I have ordered an additional one to swap out with the second part of my House RO system

Membrane was delivered quickly and in good shape. FIrst time changing on my own. Was easy to pull old and insert new. Tested water quality in PPM. Before with old membrane was 65ppm asfterwards showed 45 ppm. Perfectly in range as it should be. Price was great compared to $800 water companie wanted to come change my RO membrane. WIll definitely be ordering an extra to have on hand.

Finally installed this membrane after buying it 6 months ago. My RO system operates only on city water pressure (no booster pump). Feeding softened city water with ~550 ppm of TDS, and using a very low ~1.5x reject vs permeate flow to minimize water waste. This membrane is generating >900 ppm TDS in the reject stream and 5-8 ppm TDS in the permeate. Astounding performance !!!

Moved to the new house with well water and whole house RO system. Since I had no idea when was the last time it was serviced, I decided to replace the RO membrane. When I opened the system you can see what I found inside. Lots of biofilm, nasty. After disinfecting and cleaning out the system, new membrane went in without any issues. As to performance, I do get good TDS rejection rate, from about 400 ppm to 8 ppm, but no matter what I do, I can't get close to 2400 GPD. Best I get is about 1500 GPD, or roughly 1 gal per min, @ 78F and 150PSi pressure with a buster pump. Still good improvement as the old membrane was around 220 GPD.

I have been running 2 of these for 16 months. They are still putting out about 1.5gpm at 180psi. I would say there is no better membrane for the money. Your output will vary depending on applied pressure. But after 16 months, I am still making great water. I am running a whole home RO off of a salty west Texas well without a softener. If I installed a softener, I should be able to get about 2gpm. I will definitely be buying these again.

I have been using these membranes for years now, they work as expected and offer a good value. The claims about low water production or lack of rejection are just wrong. Permate water volume is dictated by input volume and pressure. As far as rejection of solids and other, I have my water tested by a lab every year and found that these perform 100% as they should, there is nothing in the clean water expect the mineral I add back in. Highly recommend these!!

I bought two of this membranes and they have been working for 2 years (24 months) now and still producing good water for my house 30 TDS. The production rate 2.3 GPM both membranes. I will buy 2 more for replacement.

I have been using Hydron BW 4040 RO membranes for over 6 years and always had great results with life span of about 10 to 11 months. The last two that I ordered on April 13, 2023 fouled in two weeks. Nothing in the system had changed and feed water had not changed. I ordered two more Hydron BW 4040 on May 1, 2023 and installed them on May 5, 2023. The system is now operating great. Is it possible that the membranes were defective? I would appreciate any feedback from other customers with similar experiences.