RO/DI Water

Gary LeCompte · Jul 23, 2019

Just changed my DI resins and a carbon filter.
I have been having Phosphate problems.
I have the Hanna ULR Phosphate checker.
My TDS coming out of the RODI filter is -0-.
I check the phosphate level coming out of the RO/DI and it is .23 PPM.
Any ideas of what I can do?
Could this be the source of my Phosphates problem,?
What can I do about it?

lapin · Jul 23, 2019

.23PPB as read on the meter? Or did you convert it to PPM?
I am assuming you have a clean vial that the rodi water is dripping into.

Gary LeCompte · Jul 23, 2019

lapin said:
.23PPB as read on the meter? Or did you convert it to PPM?
I am assuming you have a clean vial that the rodi water is dripping into.

this is the one that I have

212044-hannainstruments-colorimeter-phosphate-testing-fr.jpg

lapin · Jul 23, 2019

Provided your TDS meter is good and your testing is also good; some phosphate can get thru an ro/di and you can still have a reading of 0 TDS, however that amount is extreme.
My ipinion, for a solution. Throw a bag of some kind of phosphate absorbent into your container that stores the rodi water. This should reduce the phosphate but I would still look for a reason why the P04 reading is high with filtered water

Filthybum · Jul 23, 2019

How old is r/o membrane? might try replacing it

Gary LeCompte · Jul 27, 2019

Filthybum said:
How old is r/o membrane? might try replacing it

My RO/DI unit is about 8 months old.
I checked with BRS.
They said if my TDS is -0-. That is all I should worry about.
They said if you check stuff coming straight out of the RO/DI unit you will bet some crazy numbers that are not accurate.
I had dumped all my pre-new filter water and just finished yesterday filling up all new water.
The water has been sitting a while.
I need to check it and see what it says now.

LOVEROCK · Jul 28, 2019

Gary LeCompte said:
My RO/DI unit is about 8 months old.
I checked with BRS.
They said if my TDS is -0-. That is all I should worry about.
They said if you check stuff coming straight out of the RO/DI unit you will bet some crazy numbers that are not accurate.
I had dumped all my pre-new filter water and just finished yesterday filling up all new water.
The water has been sitting a while.
I need to check it and see what it says now.

what are your tds in tap?