Extending the Life of the DI Resin Cartridge/refill.

[Sophie10]

Hey All,
I've been confounded by the fact that my DI Resin cartridge has been used up at a fairly high rate, about every 3 months. I have (and had) flushed the RO membrane every month or so, and am better about changing the sediment filter and carbon block. Recently, I had a full system change out, as my RO was failing. In 3 months, my DI was used up again. I know my water is about 140 ppm from the tap, and no chloramine is used (Syracuse City). Then I read something (probably RC!) about how long and often you run your system. I used to run a lot of short (5 - 10 gallon) runs, now I'm filling a 32 g container. I always would start the water, turn on the meter and not use the water until the post RO TDS would drop from about 30 -35 ppm to around 8 ppm, and the post DI would read 0.

Now I realize what is happening. The longer the RO membrane sits, the more tap water diffuses through it and the longer it takes to run the TDS down. I believe this is why I run through my DI so fast.

So what I am now doing is bypassing the DI until the tds drops to normal , and then running through the DI and collecting the water, hoping this will extend the life of the DI resin.

So... what do you think? Anybody with similar experience and/or thoughts?
Thanks!
David

System is a 4 year old Coralife Pure Flo II 50gpd unit

 

[Sophie10]

OK, thank you very little!

 

[Buckeye Hydro]

What you are dealing with is TDS creep.

Using your RO for longer periods of time is always a good practice.

What is the TDS of your RO water (not DI water)?
Russ

 

[Buckeye Hydro]

Here are some data to illustrate the relatively high TDS in the permeate after first kicking an RO system on. These data came from two different tests.

 

[Mpfaff77]

What you doing is best thing to extend DI. I have a T off my RO. I will run system into drain till I get down to almost 0. Then will run the DI to make my water. My tap is about 80ppm and my DI is 15 months old right now. Still reads 0 and color change is about 25%.

 

[Sophie10]

What you are dealing with is TDS creep.
Using your RO for longer periods of time is always a good practice.
What is the TDS of your RO water (not DI water)?
Russ

Thanks Russ, it starts at about 35 and drops to 8ppm or a little lower.

What you doing is best thing to extend DI. I have a T off my RO. I will run system into drain till I get down to almost 0. Then will run the DI to make my water. My tap is about 80ppm and my DI is 15 months old right now. Still reads 0 and color change is about 25%.

Wow! My last one with the indicator lasted 3 months! I have just started the new one and have initiated the 'flush'! We'll see what happens.
Thanks!
David

 

[EllieSuz]

OK, thank you very little!

This might not be the best way to get help.

 

[Sophie10]

This might not be the best way to get help.

Thank Eileen. Sometimes I feel like I'm speaking to no one in general, and no one generally responds! (not mad or snarky, just a fact! :spin1: I don't even know what that spinning head means!) Love my little crappy tank, have a few years experience, know a few things, but need to hear from people who know MORE. Check my posts if you care to. I'm always thoughtful and hope to help, or offer support, or just respond to a fun OT thread. Your comment is just as helpful as mine! I say that in good nature. I will refrain from such posts in the future, but I would LOVE to hear from someone in less than week.

So, on the original post, what do you think?
Sincerely,
David

 

[solRNY]

i noticed that with my setup as well, didnt react to it then, but i think i will now, thanks for the tip!

wonder what ur water pressure at the ro membrane is, maybe were too low...

 

[Sophie10]

i noticed that with my setup as well, didnt react to it then, but i think i will now, thanks for the tip!

wonder what ur water pressure at the ro membrane is, maybe were too low...

Hmm, guess I could get a gauge in the future, but I think the water pressure is adequate. The output on the 50gpd membrane is about that - 50 gpd. I made about 50 gallons from yesterday to today, but I ran the flush of RO about an hour before using, then hooked up the DI ran another few minutes, then started collecting. That is my new protocol. We'll see what happens!
Thanks.

 

[Buckeye Hydro]

So sounds like you made 50 gallons in 12 hours rather than 24?

A add on gauge kit is dirt cheap - you're flying blind w/o a gauge.

Russ

 

[Sophie10]

So sounds like you made 50 gallons in 12 hours rather than 24?

A add on gauge kit is dirt cheap - you're flying blind w/o a gauge.

Russ

Thanks will do. I started making rodi yesterday at about 9 am, filled a 32 gallon can (about 28 gallons) and am about 4 hours from filling another can. So, it's about 56 gallons over about 28 hours.

I'll pick up that gauge. Thanks Russ!