Membrane fouling quickly...going crazy ahhhhhhhhhhh!

[intelicide]

Hello, all. I am not new to the RO scene....installed many in my lifetime, although not in the filter business. My issue involves membrane fouling. I installed a 5 stage about 8 months ago and approx 3 months ago, lost my flow and could not generate more than about 4 gallons a day with a 50gpd membrane. I checked all filters, took unit completely apart and replaced membrane only to have proper flow and generation for a month. now it has slowed back to about the same 4gpd. PSI is on target. After removing membrane, I noticed a yellowish style scale between end layers of membrane and within housing. I have lived within the Denver area for the past 3 years with no problems, although was living in another house 2 miles down the road. Is there anything I am missing, ie bad flow restrictor, auto shut off valve replacement that would impact this fouling? NEVER had this issue before...my other RO membranes always meet or exceed two years. HELP! even at a modest 19 dollars a pop on ebay adds up if i must replace membrane every month! I live in a rental so soft water system is not a solution for me....not sure whats up, TDS in denver is very low Anyone plz help! thanks and cheers!

[pawaterguy]

Hello, all. I am not new to the RO scene....installed many in my lifetime, although not in the filter business. My issue involves membrane fouling. I installed a 5 stage about 8 months ago and approx 3 months ago, lost my flow and could not generate more than about 4 gallons a day with a 50gpd membrane. I checked all filters, took unit completely apart and replaced membrane only to have proper flow and generation for a month. now it has slowed back to about the same 4gpd. PSI is on target. After removing membrane, I noticed a yellowish style scale between end layers of membrane and within housing. I have lived within the Denver area for the past 3 years with no problems, although was living in another house 2 miles down the road. Is there anything I am missing, ie bad flow restrictor, auto shut off valve replacement that would impact this fouling? NEVER had this issue before...my other RO membranes always meet or exceed two years. HELP! even at a modest 19 dollars a pop on ebay adds up if i must replace membrane every month! I live in a rental so soft water system is not a solution for me....not sure whats up, TDS in denver is very low Anyone plz help! thanks and cheers!

How does your water test? Hardness, iron, etc.

[intelicide]

have not done a water test. I will do that...did notice my feed line is turning brownish, although assumed sediment plus two carbon filters would take the brunt of the iron, etc deposits as I previously lived in Florida with much tds of lime, iron etc. What is a guess of the salt deposits forming do you think?

[pawaterguy]

have not done a water test. I will do that...did notice my feed line is turning brownish, although assumed sediment plus two carbon filters would take the brunt of the iron, etc deposits as I previously lived in Florida with much tds of lime, iron etc. What is a guess of the salt deposits forming do you think?

I doubt it's salt. It's most likely just the dissolved solids left behind. Same thing that accumulates on humidifier pads that people get excited about when they have soft water. That's a guess, mind you. I haven't seen it in person to assess anything. But, from my experience with such things it's an educated guess. Also, the iron issue depends on which type (or both) of iron that you have. Ferrous or ferric. Get some testing done and maybe there's some cheap pretreatment you can get to help the life of the membrane.

[AzJazz]

Are you sure that your brine line is draining properly? Also, do you have an air gap faucet? If not, maybe you are getting some backflow into your RO system.

[Hao Zhang]

where do you get your RO system? do they supply any cleaning chemical?