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My Tank Thread
I’m finally changing my membrane that’s somewhere in the area of 15 years old. I don’t have a pressure gauge on my old RO unit, but the TDS had creeped up from around 1-2 to 8 TDS out of the RO unit (before DI). The original membrane was a 50 gpd and I replaced that with a 75 gpd membrane. The restrictor that was there was labeled as a 550.
So I go to BRS and according to their chart I’ll need an 800 ml restrictor for a 75 gpd membrane.
I need this restrictor NOW, so I go to Amazon, and this is where it gets funky. According to their chart, a 75 gpd membrane needs a 420 cc membrane, and the 800 cc restrictor is for, are you ready, a 400/600 gpd membrane. WHAT???? That’s not even close. HERE’S the Amazon link.
I’m currently making water with the 550 restrictor with TDS at 1 prior to DI….so that’s good. But the waste water volume is up. What usually takes me 1 hour and 30 minutes is now taking 2 hours and 10 minutes to make five gallons.
Thoughts?
So I go to BRS and according to their chart I’ll need an 800 ml restrictor for a 75 gpd membrane.
I need this restrictor NOW, so I go to Amazon, and this is where it gets funky. According to their chart, a 75 gpd membrane needs a 420 cc membrane, and the 800 cc restrictor is for, are you ready, a 400/600 gpd membrane. WHAT???? That’s not even close. HERE’S the Amazon link.
I’m currently making water with the 550 restrictor with TDS at 1 prior to DI….so that’s good. But the waste water volume is up. What usually takes me 1 hour and 30 minutes is now taking 2 hours and 10 minutes to make five gallons.
Thoughts?