Copper in RODI water

[PghReef]

My ICP test just came back. Pretty good across the board but my RODI water showed some copper . Interesting enough my DT showed undetectable copper. No ill effects to tank inhabitants including my snails.

Either this number is so small that the copper added through the topoff is so miniscule its untraceable, or it's such a small quantity that it is being consumed somehow.

Could this possibly just point to my needing to replace my DI resin? Membranes, filters, all resins were replaced last August. It is a dual canister DI resin system and 1 is exhausted, the other just starting to show color change. I did accidently run warm water through the membrane for 1 hour early on after replacing. Inline TDS meter shows 0TDS.

 

[vetteguy53081]

May be from your home piping

 

[Malcontent]

How warm? If you connected it to a hot water line it's going to be more than a little warm.

 

[gbroadbridge]

My ICP test just came back. Pretty good across the board but my RODI water showed some copper . Interesting enough my DT showed undetectable copper. No ill effects to tank inhabitants including my snails.

Either this number is so small that the copper added through the topoff is so miniscule its untraceable, or it's such a small quantity that it is being consumed somehow.

Could this possibly just point to my needing to replace my DI resin? Membranes, filters, all resins were replaced last August. It is a dual canister DI resin system and 1 is exhausted, the other just starting to show color change. I did accidently run warm water through the membrane for 1 hour early on after replacing. Inline TDS meter shows 0TDS.

I wouldn't worry about it. My RODI shows about 20ppb (20ug/l) with new filters/resin.

Measured with Hanna LR copper test.

It's well below natural sea water anyway.

Regards
Graham.

 

[PghReef]

May be from your home piping

Yes just thought it would be filtered out with the 6 stage system.

 

[PghReef]

How warm? If you connected it to a hot water line it's going to be more than a little warm

I have it connected through the faucet where you turn the water on and flip the switch to run it through the rodi. I had it running and then did something and washed my hands so flipped it to the sink and put the hot on with the cold. Forgot to turn the hot off and an hour or so later when I checked the water level noticed it felt warm to the touch.

I'm not an expert but kept an eye on the TDS which continued to read 0. I assumed if I damaged the new Membrane my TDS would either rise or I'd lose some of its effectiveness and burn through DI resin faster.

 

[Porpoise Hork]

Removal of copper all depends on the inlet psi to the RO membranes, the rejection rate, and what type(s) of DI resin you are using.

 

[PghReef]

I wouldn't worry about it. My RODI shows about 20ppb (20ug/l) with new filters/resin.

Measured with Hanna LR copper test.

It's well below natural sea water anyway.

Regards
Graham.

Good to know, thank you. My last sample measured 4 months ago showed 0 so just saw the copper and was wondering if it means my filters, carbon blocks etc are getting exhausted.

 

[PghReef]

All depends on the inlet psi to the RO membranes and what type(s) of DI resin you are using.

My PSI is about 55. DI resin is the BRS resin.

 

[Porpoise Hork]

You will get a much better rejection rate with a booster pump and taking it up to 76-80 psi. The output TDS on RO side for mine went from 8 down to 2 after adding a booster pump and setting it to 78 PSI. This is on twin 150GPD membranes in water saver configuration. Total output for my system is a calculated approx 320 GPD based on time to filter 100g RODI water. This is a 1 micron sediment, twin BRS carbon blocks, twin 150 GPD membranes that feed into a PHOSBAN stage then 4 DI resin chambers. So I NEEDED the booster pump for it since inlet PSI was only about 50.

 

[HawkeyeDJ]

You will get a much better rejection rate with a booster pump and taking it up to 76-80 psi. The output TDS on RO side for mine went from 8 down to 2 after adding a booster pump and setting it to 78 PSI. This is on twin 150GPD membranes in water saver configuration. Total output for my system is a calculated approx 320 GPD based on time to filter 100g RODI water. This is a 1 micron sediment, twin BRS carbon blocks, twin 150 GPD membranes that feed into a PHOSBAN stage then 4 DI resin chambers. So I NEEDED the booster pump for it since inlet PSI was only about 50.

Wow! 4 DI resin chambers? Does the first chamber exhaust earliest? And then you rotate the chambers, put the new one at #4?

 

[vetteguy53081]

Yes just thought it would be filtered out with the 6 stage system.

Often it should or will but as media and resins start to age, they lose theyre capacity for protection and allow various compounds to get through

 

[PghReef]

Often it should or will but as media and resins start to age, they lose theyre capacity for protection and allow various compounds to get through

So is this just an issue where I need to replace my resin and filters? Like I said DT is still undetectable so it must be so diluted once it enters the system it cant register, just don't want it to build up and cause problems.

I'm still unsure of how to tell when things need changed. I know the di resin color change, when that happens I just replace the filter, both carbon blocks, and both resins. Idk how to tell if a membrane needs replaced or not though.

 

[vetteguy53081]

So is this just an issue where I need to replace my resin and filters? Like I said DT is still undetectable so it must be so diluted once it enters the system it cant register, just don't want it to build up and cause problems.

I'm still unsure of how to tell when things need changed. I know the di resin color change, when that happens I just replace the filter, both carbon blocks, and both resins. Idk how to tell if a membrane needs replaced or not though.

High likelihood

 

[bruno3047]

Dude. That measurement is 2.76 millionths of a gram per liter. I don’t think you have to worry about that.

 

[vetteguy53081]

Dude. That measurement is 2.76 millionths of a gram per liter. I don’t think you have to worry about that.

Agreed. Very low amount

 

[Porpoise Hork]

Wow! 4 DI resin chambers? Does the first chamber exhaust earliest? And then you rotate the chambers, put the new one at #4?

Most of the time it does, but have had the 2nd one change color before the 1st a couple of times. Not sure why it did that. As for the new ones, yes I put the new resin in #4 and move each up a spot. Same with the carbon blocks I pull the primary and move the second to #1 and then put the new one in #2 spot.