A Tds Meter Question

Same one I use:
Inline Dual TDS Meters

 

Good to know that I'm using the same stuff as some of tv big guys make. Me feel better

 

Hi Guys,

Keep in mind that different tap water sources have different TDS readings. This, in turn, means that the TDS coming out of the RO membrane will be different as well. A RO membrane will normally have a rejection rate between 95-99%. If you take a tap water reading of 200; at 95%, your RO TDS will be about 10 ppm. At 99%, your RO TDS will be about 2 ppm.

After the DI, though, the TDS should be zero since that's what the DI is supposed to do.

 

If your DI has color changing resin, it should be easy to tell when you're through with it. Simple, just place the housings in a vertical position. The used (color changed) beads of resin will float to the top and the unused will stay at the bottom. You can also tell by yout TDS readings. If it starts to give you a reading of 001 or 002 but you still have resin left that hasn't changed color, try shaking the DI housing(s) to get rid of any channels/air pockets that may have formed inside. After doing this, do another TDS reading and it should go back to 000. Of course, once the beads are all the same color it's time to change the resin.

 

thank for the info somehow mine doesn't come out to that number zero maybe I need to change my di resin

 

Holy crap Otty....bummer...the same at eBay for 26.95!! HM Digital DM-1 Inline Dual TDS Monitor, Meter/Tester - eBay (item 300202493635 end time Mar-07-08 15:47:12 PST)

 

Yup and free ship can't beat that

 

I think I got mine from Air Water & Ice. I just posted that link because it was all I could find real quick. Good shopping though. ;D

 

just realize, the tee that came w the tds, work w the hose that the rodi use right?

 

It looks like the right size.

About not telling if your DI is exhausted. Doesn't your DI resin change color? You should post a pic to see what your RODI unit looks like, 'cause that's pretty strange.