TDS readings at 147 post RO. Bad membrane?

Not postive but I think  18mo-2 years is about the life expectancy of the membrane.  If you changed the other filters then it does kinda make sense that the problem lies with the membrane.  Just my 2c ...

 

The only way that it's not bad is if your water going into it is over 1500 TDS...and that's assuming a 90% rejection rate. Most membranes are rated at 98% rejection rate. Sounds like it's bad to me, but it really depends on your source water.

--AJ

 

True AJ! Bad Membrane.... Try bulk reef supply they have a great exp. on how to tell if your membrane is shot. Hope that you have not been using that for your reeftank! I wouldnt use that for my morning coffee! LOL! @ 10-20 ppm coming through your rodi you get 5-10 ppm of nitrate and others! good luck and post your results also mabe try a second tds meter.

 

Posted By rvarner on 08/22/2009 09:38 PM
Just got a TDS meter from Air Water and Ice, and my post RO readings are around 147.  My membrane is about 2 years old, but has new filter cartridges, except for DI which is a little over half color change.  Wondering if my membrane is probably shot.                                                                 Ryan
What's the TDS of the water from the faucet?  Wondering if the meter is properly calibrated...I would try and test some different water.  Go to Wal-Mart - there's should test just shy of 50 !
I had a problem in March when I filled my tank with an old (2.5 yrs) membrane.  I was getting around 80 TDS, replaced everything but the membrane and it only lowered it to 34.  After replacing the membrane it went down to zero.
If the reading is actually that high, it sounds like there's possibly a tear in the membrane.
147 is insane...in the membrane  
-Eric

 

go to filterguys.com they have a very cost effective duel inline tds meter... for like only $30 you can read the before the DI which is right outta the membrane then after the DI and they ready your end result... I bought one it was the best purchase i made...

 

Sure. Post your used unit on the Buy/Sell forums and I'm sure someone will be willing to buy it and refurbish it. You remembered your 10% club discount, right?

--AJ

 

Cool! Congrats on your new purchase!

--AJ