skp
New member
Hi Guys,
My DI is used up, so I'm replacing it but I'm not sure if I should replace the ro membrane. The ro membrane has been used for 5 years making about 3.5 gallons per day. My tap water is at 15 tds and the water coming out right after the membrane is at 2. That means it has a rejection rate of less than 86% and I've been reading that it should be changed when the rejection rate drops below 90%. I didn't test the rejection rate when it was new but I've used a 2 canister ro system without the di before and it was always around 2-3 where I live and I remember hearing/reading that it's normal to get a tds of 2-3 with just ro.
My DI is used up, so I'm replacing it but I'm not sure if I should replace the ro membrane. The ro membrane has been used for 5 years making about 3.5 gallons per day. My tap water is at 15 tds and the water coming out right after the membrane is at 2. That means it has a rejection rate of less than 86% and I've been reading that it should be changed when the rejection rate drops below 90%. I didn't test the rejection rate when it was new but I've used a 2 canister ro system without the di before and it was always around 2-3 where I live and I remember hearing/reading that it's normal to get a tds of 2-3 with just ro.