Well water CO2 content

Mkrizzz83 · Feb 16, 2020

I’m in the initial planning stages of setting up my first reef tank and am located on the northern of Milwaukee County but have a well. I’m building my RODI making / salt mixing station but have just found that dissolved CO2 can cause issues with extremely fast DI resin anion consumption. I was wondering if anybody currently using well water for their tanks knows how to test for this.

I have had the well tested recently for the normal DNR required information (nitrate, arsenic, etc) and it all came back normal. I know there is a way to bubble off CO2 with an air stone before it enters the DI stage but was hoping to avoid this unless necessary.

So is there a way to test for CO2 in water or a surrogate test like pH, alkalinity, etc? It would be especially helpful if anyone near Milwaukee county on a well could chime in with their experience. Thanks in advance!!

Matt

reef lover · Mar 18, 2020

Bump!

Mkrizzz83 · Mar 18, 2020

Thanks for the bump. What I ended up doing was getting a 7 stage RODI filter with separate anion and cation resins. I really was not up to creating a degassing stage prior to running the water through the DI. I have made about 30 gallons of water with only a barely noticeable color change in the anion resin. Anion resin isn’t that expensive and I’m hoping the cost of separating the resins (with more frequent anion replacement) will make up for figuring out how to plumb in a degassing station.
Matt

RobB'z Reef · Jun 15, 2020

ha! I'm just going thru this myself! I'm in western WI on a well and my new BRS DI cartridge went **** up after 100 gallons on a completely new system. Oddly enough I had a culligans water guy over doing maintenance on my softener and he used his TDS meter to check the supply which only came in at 144 which i thought... not too shabby. I been making it in bulk, like 30 gallons at a time so it wasn't like a small batch thing. He talked about CO2 well content just like you mentioned. I'm not having the stomach for setting up yet another tank to aerate water either.
I did order another dual canister mount and now could potentially do the split resin setup. So you're seeing the CO2 effect the anion only then? If that's the case, I wonder if i could do two anion cartridges in a row (rotate those as they deplete) and then a mixed bed in the final one. My TDS was measuring 8 going into the single mixed bed DI cartridge and zero after (before depletion).

92Miata · Jun 15, 2020

They make whole-house iron filters - they're basically just a giant aerator that runs before your water softener. They're about $500-600 for a whole house system - which is pricey for pre-treating your water- but if you're chewing through $15 worth of resin every 30 gallons, it might be worth looking into.

Mkrizzz83 · Jun 15, 2020

Hey thanks for the reply. Thanks to covid and a new baby on the way, the reef plans and hence water making are currently at a halt. I’ve made about 60 gallons of RODI water in total and the bottom inch or so of my anion started to change color. I haven’t used the DI in a while and that color changed actually disappeared. There was no noticeable color change in the cation resin. I am not an expert but I have had good limitedresults with three resin chambers. Cation->Anion->Mixed. Should save money in the long run as well as resin changes are more specific to needs. Good luck.
Matt

Mkrizzz83 · Jun 15, 2020

I have an iron curtain as previously mentioned as well.

Randy Holmes-Farley · Jun 15, 2020

Measuring pH and alkalinity give you CO2 in well water:

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How do I calculate CO2 and its effects on DI water production?

RobB'z Reef · Jun 15, 2020

Randy Holmes-Farley said:
Measuring pH and alkalinity give you CO2 in well water:

Helpcenter

spectrapure.com

scroll down to:

How do I calculate CO2 and its effects on DI water production?