New ro/di spectrapure

Cory · Mar 1, 2018

I wonder if my hm digital dual inline tds meter is accurate? Does a high silicate rejection membrane help with lowering tds compared to dow filmteks?

Previously on my 24gpd watts premier ro unit with a rejection rate of 98% (dow filmtek) i got 8-20ppm depending on source tds. Now with the spectrapure Its registering 1-3 tds. Im not sure how efficient they are, but wow that's a big difference.

Randy Holmes-Farley · Mar 1, 2018

Cory said:
I wonder if my hm digital dual inline tds meter is accurate? Does a high silicate rejection membrane help with lowering tds compared to dow filmteks?

Previously on my 24gpd watts premier ro unit with a rejection rate of 98% (dow filmtek) i got 8-20ppm depending on source tds. Now with the spectrapure Its registering 1-3 tds. Im not sure how efficient they are, but wow that's a big difference.

I doubt the silicate is a primary driver of the TDS after the membrane (since there will be a lot of other ions too, and possibly at higher concentration), so you might not notice the effect even if the effect is substantial in terms of more silicate rejection. It may just be better at rejecting everything.

redfishbluefish · Mar 1, 2018

I'm not sure if I can answer your question. Are you using the same TDS meter with the Spectrapure?

If the Dow Filmtek was truly a 98%, the 8 - 20 TDS would calculate to a raw water TDS of 400 - 1000, respectively. That's a pretty large range! Do you actually know your raw water TDS?

Bottom line, Spectrapure is top notch with water purification. You can't go wrong with a Spectrapure RO/DI unit.

Cory · Mar 1, 2018

Yes its the one that came with it.

I havent read the tap water yet but your right its usually in that range.

Im pretty impressed with this unit.

Cory · Mar 1, 2018

The deion resin is tan color. Is it color changing?

Cory · Mar 1, 2018

Randy Holmes-Farley said:
I doubt the silicate is a primary driver of the TDS after the membrane (since there will be a lot of other ions too, and possibly at higher concentration), so you might not notice the effect even if the effect is substantial in terms of more silicate rejection. It may just be better at rejecting everything.

This was my ro