dive into the sediment and carbon blocks question

[ddc0715]

i have this very setup running right now. including a auto shutoff valve and a tds meter located pre and post resin chambers.

i changed out everything yesturday. membrane, resin sediment filters and carbon blocks.

so today i had and installed a spare 2 port tds meter at my source water line (the yellow star location) and the out port just before it enters the membrane (the blue star)

anyway-- let the exsperiment being.
the yellow star or my souce water from the tap reads 99
the blue star, post filters/entering my membrane has a tds of 115
the red star, pre resin has a tds of 2
the green star of post resion has a tds of 0

my question is ---why is/would the tds that is entering the membrane/ existing the fiters (blue star), be higher than my source water (yellow star)?

 

[Dan_P]

i have this very setup running right now. including a auto shutoff valve and a tds meter located pre and post resin chambers.

i changed out everything yesturday. membrane, resin sediment filters and carbon blocks.

so today i had and installed a spare 2 port tds meter at my source water line (the yellow star location) and the out port just before it enters the membrane (the blue star)

anyway-- let the exsperiment being.
the yellow star or my souce water from the tap reads 99
the blue star, post filters/entering my membrane has a tds of 115
the red star, pre resin has a tds of 2
the green star of post resion has a tds of 0

my question is ---why is/would the tds that is entering the membrane/ existing the fiters (blue star), higher than my source water (yellow star)?

Do the two TDS meters read the same when their probes are in the same water sample?

 

[ddc0715]

i will test and let you know. i wondering if the carbon blocks are breaking up /lose or maybe carbon block dust.

 

[SPS2020]

Interesting and following.

 

[Mark Gray]

Following I have the same setup.

 

[DCR]

The TDS meters are just very cheap conductivity meters. They are based on a correlation between TDS and conductivity, but it is not an exact correlation. Different ions contribute different values to the overall conductance. Your carbon filters may be absorbing some materials while releasing others that contribute to a higher conductivity. I would also question the accuracy of these TDS meters, especially at high levels that they really are not intended to test at. I think 99 and 115 may effectively be the same number for these analyzers.

 

[Buckeye Hydro]

i have this very setup running right now. including a auto shutoff valve and a tds meter located pre and post resin chambers.

i changed out everything yesturday. membrane, resin sediment filters and carbon blocks.

so today i had and installed a spare 2 port tds meter at my source water line (the yellow star location) and the out port just before it enters the membrane (the blue star)

anyway-- let the exsperiment being.
the yellow star or my souce water from the tap reads 99
the blue star, post filters/entering my membrane has a tds of 115
the red star, pre resin has a tds of 2
the green star of post resion has a tds of 0

my question is ---why is/would the tds that is entering the membrane/ existing the fiters (blue star), be higher than my source water (yellow star)?

Nothing unusual in your numbers. Remember the sediment filter and carbon block(s) don't remove TDS.