Why am I burning through DI Resin?

[TheEngineer]

I can't figure out why I'm burning through DI resin and I'm hoping someone can tell me why. My incoming TDS is 58 and outgoing is 0. I am running a booster pump at 90 psi. After making about 45 gallons of water I burned through a canister and a half of DI resin (maybe 1/2 lb). I don't think my RO membrane is hooked in backwards, but that's the only thing that is coming to mind....

Here's a pic of my RO membrane hookup. You can see the flow restrictor on what I am hoping is the drain side. Based on flow rates, it sure seems to be. That DI canister you can see was solid blue before I started making water this AM and now it is fully depleted and the one next to it is 25% done.

 

[Downbeach]

Are you on well water? CO2 maybe?

 

[TheEngineer]

Yep I am. My pH is low out of the well.

 

[Downbeach]

That's most likely the problem. Many wells have a hi CO2 level, and will burn through your DI resin in no time. If I remember, Hach and LaMotte both make a CO2 test kit. You'll have to do something to gas off the CO2 before it enters your DI chamber.

 

[vedros74]

I think downbeach is correct. I'm not on well water and I go through DI fast and I called spectra pure who makes my system and they said the exact same thing that high CO2 is the main thing that will deplete the resin. I was told to break up the CO2 before it enters your filter the best thing is to put it in a drum or container with a pump and mix it up before it goes through the filters

 

[TheEngineer]

Dang it, dang it, dang it! Well at least I only went through like $15 worth of resin and didn't blow up something expensive. Thanks for catching that Jim and vendros74.

Since I'm already using a booster pump, I would just need a container for the water and powerhead. Mix for 24 hours?

Where does one buy such a container? In the long run, 5g should be plenty and I'll get a 5g pressure tank so I'll have 10g relatively ready to go at any time.

 

[vedros74]

I'm sure any food safe plastic container from lowes or Home Depot with a powerhead to mix it would be good. Not sure on the mixing time I'm sure 24 would be more than enough

 

[Downbeach]

It might be better to use an MJ1200 with the venturi, clip it toward the top of the container and let it run overnight.

 

[kschweer]

I would agree with the high co2. What I would do is run the water through all stages of your ro except di first, then aerate for 24hrs, and finally pump it through your di resin.

 

[TheEngineer]

I'm sure any food safe plastic container from lowes or Home Depot with a powerhead to mix it would be good. Not sure on the mixing time I'm sure 24 would be more than enough

OK. That's easy enough.

It might be better to use an MJ1200 with the venturi, clip it toward the top of the container and let it run overnight.

Definitely have a MJ1200 around here somewhere. Could I just use an air stone?

I would agree with the high co2. What I would do is run the water through all stages of your ro except di first, then aerate for 24hrs, and finally pump it through your di resin.

Hmmm... What would I use to pump through the DI chambers? I need to pump the water up one floor from my basement too.

 

[SPSREEFS]

I am curious, is the well water very hard??? High calcium levels will wipe out a DI cartridge in a hurry! You have to soften the water first.

 

[kschweer]

An air stone should work for you. Something like the maxijet 1200 would be enough to pump water through the di and then use a bigger pump to pump it upstairs.

 

[bobman]

Also you will need to know your rejection rate on the system. If you need 5 gallons of rodi water it will take alot more in the container to make up for the rejected water.

 

[kschweer]

Also you will need to know your rejection rate on the system. If you need 5 gallons of rodi water it will take alot more in the container to make up for the rejected water.

Exactly. That's why I would say to run water through all stages except di before aerating and then through the di.

 

[TheEngineer]

I am curious, is the well water very hard??? High calcium levels will wipe out a DI cartridge in a hurry! You have to soften the water first.

No it isn't. The only two things off in my water are low pH and high lead content. A pH buffer and water softener (for the lead) are in the plans. I thought the RO membrane pulls minerals (like calcium) out. Would it make it through to the DI?

An air stone should work for you. Something like the maxijet 1200 would be enough to pump water through the di and then use a bigger pump to pump it upstairs.

OK. I'll have to rig something up to mate the MJ to the DI. For now I'll just haul buckets I guess.

Also you will need to know your rejection rate on the system. If you need 5 gallons of rodi water it will take alot more in the container to make up for the rejected water.

Indeed! I'm at about 3.5ish to 1 (input to RODI out). The idea of storing the RO water makes a lot of sense.

 

[Downbeach]

This might be a little more than you need, but maybe it will give you some idea's.

http://spectrapure.com/manuals/CO2_SYSTEM.pdf

 

[TheEngineer]

That's very helpful! Gives me a good picture of what to strive for. I don't know if I'll automate it like that, but something similar.

Guess I'm going to just finishing plowing through the resin that's in there at this point so I can finish filling my tank up. My "30g" brute only filled my 50g tank with rock and sand in it about half way... Me thinks I bought a smaller can than I remember

 

[SPSREEFS]

Hi calcium levels will not effect the membrane to my knowledge. I have never had a issue with my RO membrane at all. However, hard water will wipe out the DI resin extremely fast. You don't have to buy a water softener. You can have a company come out and install a softening tank for you. They will come out once a month and replace the tank that has been recharged. I pay 40 a month and installation was free!
You need to test the well water with a calcium test kit to see what numbers you get.

 

[TheEngineer]

Thanks for the suggestion. It's cheap enough to put my own system in. At $40/month, I'd pay the softener off in under a year. It's only $390 for the softener and it will run about another $30-50 in salt per year. The whole system, pH neutralizer and softener, will run me around $1000 and I can plumb it myself.

Thinking about that... would my CO2 go down enough through the softener system? I could put an airstone in the brine tank.

I made about another 15 gallons of water and my DI resin is totally dead now and my TDS is at 3 ppm. Pfft... could have bought water for less than that.

 

[habutti]

Okay, I'm on well with a softener in my house. I had my RODI system setup with a 44g brute and a float valve and all every week I fill that brute with rodi water, I spent a cartridge of di resin. Called spectra, marine depot, BRS, watched every single video on the web.
The fix - I purchased another brute container (3 total, one for ro water, di water, salt water). Purchased a cobalt MJ1200 pump/powerhead, purchased an air pump with long piece of tubing and an air stone (all can be found second hand for pennies on the dollar or even gifted from your local club).
Make RO water and drop the airstone and power head and let them go to town jn the water for at least a day (2 days for me, all Wednesday and Thursday). Thursday night I convert the MJ1200 from powerhead to a pump, and pump the RO aerated water through the DI resin cartridge (I have a valve on the line to adjust flow) make sure you allow enough time for contact between the water and the resin or it won't work (a TDS meter helps must read zero on the output). By Friday after work all the RO water should be through the DI resin and ready for mixing with salt for the weekend water changing activities. About a water softener, call the vendor they will come out and test your water for free, and let you know if you need one for your well. I'm not sure that a water softener will solve the CO2 issue, cause I have them both, the softener and CO2.

This is all you need in addition to your water containers: