R/O water smells skunky

[Reef Pilot]

While my tds after DI is always 0, the tds after RO (before DI) will climb to 10 or more if I don't open the bypass valve and flush the membrane. Like I said, I usually do it when I see it climb to a few ppm, and then it is back down to 0 after the flush. Normally, my gauges show 0:0 or 1:0.

The water out of my tap in Langley is about 50 tds normally. However, it must be higher at times (although haven't caught it in a test), because my sediment and carbon filters still need to be changed about every 4 months or so. I can tell when they need changing because my flow slows down, and it takes longer to fill the pressure storage tanks. And I am always amazed at the red/brown sediment in the pre-filters, despite the seemingly clear tap water.

I still don't think fast flow through the DI is a problem though, as I have that with my RO pressure storage tanks. I do agree though, you should have an RO membrane.

[mike31154]

With TDS 50 at source, DI only would probably not be economical. I've heard some of you on the west coast have TDS 10 or lower though, so it might be an option for those lucky few.

[Reef Pilot]

Originally Posted by mike31154

With TDS 50 at source, DI only would probably not be economical. I've heard some of you on the west coast have TDS 10 or lower though, so it might be an option for those lucky few.

Just checked my tap water and it is 64 at the moment. Have never seen it at 10 in Langley. I understand they also supplement here with well water (not sure why as we are tied in with the Metro Vancouver water supply).

Back to the OP question, here is some info on DI replacement from the manufacturer of my RO/DI unit.
http://www.airwaterice.com/category/z.2/

I have this unit, but with the 75 gpd membrane. I bought it used and still going strong.
http://www.airwaterice.com/product/1...TDS-Meter.html

[Rogue951]

I'm in east van and I average 16ppm. My membranes usually last a few years, usually I change it out of age rather than use. Same with the prefilters. easily 6 months between changes.
except this summer a few houses in my area were torn down rebuilt with water main work and I've noticed the sediment filter change color so I've swapped them out faster. Water also smelled a little different but nothing alarming.
Maybe you had construction in your area to cause a spike in impurities?

We're really lucky out here never realized it till I saw the value's of other places.

[gregzz4]

Adam, besides your membrane possibly needing replacement, it's possible you need to sterilize your system due to bacteria
If this is the case, you'll need to replace all your filter media

Buckeye Field Supply suggests this method;

We recommend sanitizing your RO/DI system approximately once per year. Schedule this process at a time when you are planning to replace your cartridges. These instructions apply to water purification systems without a pressure tank. Before you begin assure that you have about an hour available, and that your work area and hands are clean.

Turn off the water supply to the system.

Remove all housings and remove all pre-filters and post-filters from the system including sediment filters, carbon filters, in-line filters, and deionization cartridges. Remove the reverse osmosis membrane(s).

Wash housings with a soft brush or cloth in warm soapy water. Rinse thoroughly to remove all soap. Don't forget to carefully remove and wash all o-rings. Lubricate the o-rings with a small amount of silicone grease and reinstall them.

Fill each vertical housing with one cup of potable water and three to four tablespoons of household bleach, and with this sanitizing liquid still in the housings, screw them back on to the system.

Turn on the water supply a bit, allow water to fill the entire system, and assure water is flowing out of the waste line and the purified water line. Place the outlet of the drain tube and purified water tube slightly higher than the system to assure these tubes are full of the sanitizing solution. When the sanitizing solution has reached the outlet of each tube, and with the outlet of each tube placed above the rest of the system, shut off the water supply for 30 minutes.

After 30 minutes, turn the water supply on and assure that water exits the system from both the drain tube and the purified water port. Flush the sanitizing solution from the system for 5 to 10 minutes.

Turn off the water supply and install new filters, taking care to flush the filters as appropriate.

We recommend keeping a maintenance record for your system. Record the date of the sanitizing and filter replacement.