How do I get rid of tin from RODI water

Rcollick · Nov 21, 2019

I just had a ATI ICP test done and it’s coming back with elevated tin. Is there any way to overcome this? My TDS readings are always 0. The sample came straight from the good water line. It was never stored or taken from a holding container. My levels in my tank are about exactly the same. I’m pretty sure it’s coming from my RODI water. Sorry I’m not sure how to download the whole file.

AllSignsPointToFish · Nov 22, 2019

Have you tried running some Seachem Cuprisorb in your tank? Cuprisorb is formulated specifically for copper but also removes other heavy metals.

An additional cation-only removal step may also help.

Rcollick · Nov 22, 2019

I haven’t tried cuprisorb yet. I’m pretty sure it’s from my RODI water getting into the tank. I do have a 6 stage RODI unit. Sediment filter, carbon block, membrane, cation resin, anion resin then mixed bed resin. All filters look to be good. I don’t know how anything would be getting by. Coming from well water with around 350 tds. Final water always shows 0 tds.

HM3105 · Nov 22, 2019

GAC will remove organotin if it's leaching from a housing or piece of tubing.

Cuprisorb will remove regular tin, I would think your carbon block would be picking up any tin from the water source.

AllSignsPointToFish · Nov 22, 2019

4 ppb is a pretty small amount when you consider that's been concentrated in your tank. The amount in your DI water is probably a lot lower.

I don't know of many technologies out there for removing ppb levels of heavy metals that wouldn't spoil the quality of your DI water.

Are you even sure tin at those levels is an issue or is causing any problems in your tank?

Rcollick · Nov 22, 2019

The 4ppb results are from my RODI water. Test results for the tank water was about exactly the same. No issues with the tank. I just thought it was something to be concerned with.

AllSignsPointToFish · Nov 22, 2019

Oh, my misunderstanding! I thought that was tank water.

If it's not causing any issues, I wouldn't worry about it. Probably the easiest/safest thing to do if it does bother you is to try some Cuprisorb in the tank to see if the tin levels are reduced. The nice part about the Cuprisorb is that it can be regenerated if it works

Randy Holmes-Farley · Nov 24, 2019

Rcollick said:
The 4ppb results are from my RODI water. Test results for the tank water was about exactly the same. No issues with the tank. I just thought it was something to be concerned with.

I wouldn't be over focused on the RO/DI itself as I expect it is not the primary source. The numbers you show for your RO/DI suggest to me it is coming post RO/DI. Maybe from plastic pipes you run it through.

The tank level, if the same, isn't especially high and the top off water is only adding a tiny bit since you top off probably only 1-4% daily.