Rodi upgrade needed?

[Reef Wizard]

Backstory: Ever since moving into our new house my di resin in specific is getting brown very quick. I changed the resin a little over a month ago. See picture of new cannister. While I did just fill up a 200g system lol. This is probably the whole reason its used this much but, the cannister before that wasnt used heavily and was producing 2 TDS after about 4 months this one is still at 0 but the previous was still used quick my pressure is fine. I'm wondering if its because its an older house and I believe we have copper pipes.

So question is should I get a second di resin cannister? Current is a 5 stage 150 gal per day water saver
Is it worth getting a refillable cannister and refilling resin manually or should I just get pre-made ones?

 

[Jason_MrFrags]

Have you tested the TDS at the tap? and what it is after your membrane? to make sure your getting good rejection rate

 

[brclark82]

First, you already have a refillable cannister inside that unit so you can buy bulk and repack your self.

Second, another DI canister isn’t going to decrease your resin usage, but it will allow you to waste a little less by fully depleting the first cartridge before replacing.

Third, what is your TDS after your RO, it should be less than 5-6 or so and if that’s the case you have CO2 in your water and nothing short of degassing before your DI will decrease usage

 

[Reef Wizard]

Have you tested the TDS at the tap? and what it is after your membrane? to make sure your getting good rejection rate

Yeah I have its around 60-70 TDS at the tap.

 

[Reef Wizard]

First, you already have a refillable cannister inside that unit so you can buy bulk and repack your self.

Second, another DI canister isn’t going to decrease your resin usage, but it will allow you to waste a little less by fully depleting the first cartridge before replacing.

Third, what is your TDS after your RO, it should be less than 5-6 or so and if that’s the case you have CO2 in your water and nothing short of degassing before your DI will decrease usage

Ok so just tested after RO and its at a 24 TDS. So besides CO2 in the water how often should I replace the RO filters? The only use they have had is about 10 months worth

 

[Reef Wizard]

Have you tested the TDS at the tap? and what it is after your membrane? to make sure your getting good rejection rate

So 60-70 at tap and after RO and its at a 24 TDS. So besides CO2 in the water how often should I replace the RO filters? The only use they have had is about 10 months worth

 

[Gumbies R Us]

So 60-70 at tap and after RO and its at a 24 TDS. So besides CO2 in the water how often should I replace the RO filters? The only use they have had is about 10 months worth

Here is a link to BRS that talks about when to replace RO filters

 

[rhitee93]

If you are only at 60-70 from the tap, and still at 24 after your RO stage, you may have a membrane problem. Rejection ratio should be much higher than that. I would expect something like 2 TDS going into your DI resin.

 

[Reef Wizard]

If you are only at 60-70 from the tap, and still at 24 after your RO stage, you may have a membrane problem. Rejection ratio should be much higher than that. I would expect something like 2 TDS going into your DI resin.

I added a second membrane to produce more GPD a few months ago. Its not leaking or anything. How would I know if there is a problem with that? Open up and inspect membrane? or what.

 

[rhitee93]

I added a second membrane to produce more GPD a few months ago. Its not leaking or anything. How would I know if there is a problem with that? Open up and inspect membrane? or what.

I'm not sure, that is beyond my experience level. However, the rejection rate of your membranes should be in the high 90% range. Mine runs around 98%, but I think I've seen people say 96-98% is typical.

How did you plumb in the second membrane? Maybe there is an issue there. Can you easily take the 2nd membrane offline and measure the TDS coming for just the original one?

 

[Reef Wizard]

I'm not sure, that is beyond my experience level. However, the rejection rate of your membranes should be in the high 90% range. Mine runs around 98%, but I think I've seen people say 96-98% is typical.

How did you plumb in the second membrane? Maybe there is an issue there. Can you easily take the 2nd membrane offline and measure the TDS coming for just the original one?

its installed per instructions on top of the first membrane and lines are routed as listed from instructions.

And Let me see if I can remove the second

 

[Jason_MrFrags]

Yes looks like your having some issue with a RO membrane.

What brand are you running?

You said your running a 2nd after the first to boost your production. Have you tested all the pressures?
1. Tap
2. After your prefilters/before 1st membrane
3. Before 2nd membrane


I personally have run a booster pump for years. Really helps the membranes perform better and produce more water.

 

[Reef Wizard]

its installed per instructions on top of the first membrane and lines are routed as listed from instructions.

And Let me see if I can remove the second

Yes looks like your having some issue with a RO membrane.

What brand are you running?

You said your running a 2nd after the first to boost your production. Have you tested all the pressures?
1. Tap
2. After your prefilters/before 1st membrane
3. Before 2nd membrane


I personally have run a booster pump for years. Really helps the membranes perform better and produce more water.

So I removed the second membrane and I get 10 TDS after the RO with a single membrane. I do have a booster I can use but not anywhere to really plug it into an outlet

 

[KStatefan]

What are the specs for the membrane rejection rate?

You said your pressure is fine, what does that mean?

 

[Reef Wizard]

So I removed the second membrane and I get 10 TDS after the RO with a single membrane. I do have a booster I can use but not anywhere to really plug it into an outlet

What are the specs for the membrane rejection rate?

You said your pressure is fine, what does that mean?

5 Stage Premium Plus 75 GPD RO/DI System - Bulk Reef Supply is what I originally bought. I upgraded to the water saver kit

I mean pressure isnt overtly low its around 65 psi per the gauge

So an update I flushed the single membrane for a min and it from 10 to 2 TDS. So currently i am installing the second back and going to flush it as well.

 

[Reef Wizard]

SO UPDATE: Im sure it was the second membrane when I installed it because I had to reseat it before I ultimately started using it. I cant recall if I flushed it after reseating so I just flushed both membranes now and im getting 2 TDS from RO through both membranes.

So im going to chalk this up as solved.

I will have to get some new DI in there shortly but this will reduce resin consumption considerably

Thanks everyone for the help and input

And PSA Dont forget to flush ladies and gentleman

 

[rhitee93]

Glad you got it sorted.

Per one of your original questions, you can buy the bulk resin and refill the cartridge you have. However, no faster than you will use resin at 2tds, I'm not sure I would bother. I find refilling the resin to be a pain.

I buy the bulk resin and refill my own because I have high CO2 in my water which burns through the anion resin very quickly. (You may still find the same) I run separate resin beds because of this, and have to refill the anion cartridge every 200 gallons or so.

 

[Gumbies R Us]

SO UPDATE: Im sure it was the second membrane when I installed it because I had to reseat it before I ultimately started using it. I cant recall if I flushed it after reseating so I just flushed both membranes now and im getting 2 TDS from RO through both membranes.

So im going to chalk this up as solved.

I will have to get some new DI in there shortly but this will reduce resin consumption considerably

Thanks everyone for the help and input

And PSA Dont forget to flush ladies and gentleman

Glad you got it all sorted out!