Help me understand when is best to change which filters on my RODI unit please.

[fishbox]

I'm new to this. So bare with me friends. This is going to be long LOL.

I purchased and installed the 4 stage BRS value plus RODI system 7 mos ago. About a month ago (maybe two) my TDS started to creep up from 0 and I'm now up to 6. At the same time the TDS started creeping, I had to relocate the tank and started battling diatoms or dinos (not sure which). So I need to know if it's related to one of these filters or the move or both. If it's related to filters I'd like to know which particular filter it could be related to. I'm fully aware that the general consensus is to change the sediment filter and the DI resin at 6 months and the carbon blocke at 1 year. However I am also fully aware that it can be more economical for me to know exactly when and why to change each filter.

So let's start with the sediment filter. I've read that it should be changed at 6 months or when clogged which can be indicated by low pressure or color change to brown. Well yes it has been 6 months but it has not changed color at all it is pure white and my pressure has always been between 70 and 80 psi and remains there. So should I change it just because it's been 6 months and I have TDS? And could this filter have anything to do with any of the two algae I mentioned above?

Now let's talk about the carbon block. From my understanding the carbon block needs changed every year or when the chloramines start to creep up. Well we're not quite at a year yet and my incoming chloramines from my tap water only measure at 0.5. I checked the chloramines on the product water and the Wastewater and got 0 at both. Just want to verify that I'm correct that this has nothing to do with my TDS and I'm not having to replace this but could this filter be the cause of one of my algae above?

As far as the DI resin goes, I know they recommend changing it at 6 mos. So it's due but it has not completely changed colors. Only a small portion has changed. I'll include a pic, but can this be the source of TDS and/or algae?

Then there is the membrane. I know they say 2-3 yrs. So I doubt at 7 mos it's an issue, but I have no idea how to indicate when it's truly bad. Can you tell me?

My last question is in what sequence of filters does the water flow through these filters?

I apologize for such a long thread with many questions just trying to learn as much as I can and cover my questions.

 

[cmcoker]

Flow is sediment > carbon > membrane > di resin.
If your up to 6 in the finished water, change the di resin.

Change membrane when it is 95% rejection or lower, use tap tds and TDS after membrane to determine rejection rate.

Sediment filter changed when pressure drop, they're cheap so I usually will replace when I am doing carbon cause it's easier to break system down once.

I change carbon filters every 6 months because I'm not good about testing for them.

Silicate could be breaking through your di and causing diatoms, not sure without test but changing the di and see if it dissipates will tell you.

 

[Salty1962]

Flushing your membrane helps TDS creep

 

[fishbox]

Flushing your membrane helps TDS creep

I let it flush for 1 min before and after usage. Is this good enough?

 

[fishbox]

Change membrane when it is 95% rejection or lower, use tap tds and TDS after membrane to determine

I'm a little lost here [emoji23] do I just disconnect the DI portion and test there? I assume I'll need a handheld TDS meter as I only have the inline meter. So if I see any TDS here it's time to change?

 

[fishbox]

I change carbon filters every 6 months because I'm not good about testing for them.

But am I correct that I don't need to change this because it should last 1 yr and I'm at 7 mos and I'm not seeing any chloramines in the Wastewater?

 

[fishbox]

Sediment filter changed when pressure drop, they're cheap so I usually will replace when I am doing carbon cause it's easier to break system down once.

I understand the filters are cheap but I'm a non-working full time college student. So I am nickeling and diming this tank LOL. So again I'm correct that I do not need to change this because my pressure is just fine? How much of a pressure loss should I be looking for to recognize a time for change? Again my pressure is usually between 70 and 80 let's just say 75 on average.

 

[PatW]

I measure my tds before it goes into the RO membrane and after. Mine runs at about 120 going in and 2 going out. It is always 0 tds after coming out of the resin. I use color change resin so I know when to change it. It does not sound as if your sediment filter or carbon filters are a problem. I doubt that your RO membrane would be a problem in the short time you have been running. The other thing is the DI resin. I get about 200 gallons per DI canister.

 

[jimmyzhou]

I got the same unit as u have to get the right maximum proformace for this 150 plus 4 stage. U need min 65 psi too maximum the life and proformace for this unit will replacement them every 6 month. With m and carbon. Di depends.. on your water.
I buy 2 extra di canisters to upg to 6 stages. Re do the tube on the 150+ with 2 carbon Canister 1-3 first than membrane. Than 2 di. Soo far 30 gallon rodi per weeks use for 3 month soo far di still like new. In tds 17. Out tds 0

 

[fishbox]

My tap water TDS is only 27. So I would have thought the DI resin would have lasted longer than 6 mos. And the color has not completely changed colors. I placed the order for new DI resin.

 

[jimmyzhou]

My tap water TDS is only 27. So I would have thought the DI resin would have lasted longer than 6 mos. And the color has not completely changed colors. I placed the order for new DI resin.

Some time the color can’t tell 0 tds or not. First I will check psi. If 75gph. Around 45-60 psi that’s nice with out booster pump. If not I use use booster pump. High psi will helps save more water produce more ro and keep membranes longer. Make sure flash the membrane for 1 min before use. And before shut off to get the best proformace of this unit

 

[cmcoker]

My tap water TDS is only 27. So I would have thought the DI resin would have lasted longer than 6 mos. And the color has not completely changed colors. I placed the order for new DI resin.

Did you use a hand held meter? The inline ones can be inaccurate, they don't compensate for temperature.

A couple things could happen to make you deplete di resin faster than assumed.

1. Channeling in the resin, if it's not packed appropriately water can flow through certain areas bypassing the rest of the resin. That would deplete the areas it's channeling through and allow the rest of the resin to go unused.

2. High CO2 in source water, this would cause the di resin to deplete quickly and requires a degassing chamber to correct.

3. Improperly seated to membrane. If your tap is really only 27, but is bypassing the membrane then you are sending that 27 TDS water to the resin.

4. Improperly configured water lines. Occasionally people will accidently switch the product line and the waste line.

To test after the membrane, yes just disconnect the line to the di resin.
I'd use a glass container to collect the sample, rinse several time with rodi water, then collect the sample and take a reading.

I change sediment when I get a drop to 60psi, I usually got in 70-75psi.

I believe testing the waste water for chlorine is the best way to gauge carbon. I have the lamotte total chlorine/chlorine test strips( just bad about using them, lol). You can get them at bulkreefsupply for $11 or 12

 

[Reefrookie220]

6 months or 3000 gallons whichever comes first. That's the rule I've always went by.

 

[fishbox]

Did you use a hand held meter? The inline ones can be inaccurate, they don't compensate for temperature.

A couple things could happen to make you deplete di resin faster than assumed.

1. Channeling in the resin, if it's not packed appropriately water can flow through certain areas bypassing the rest of the resin. That would deplete the areas it's channeling through and allow the rest of the resin to go unused.

2. High CO2 in source water, this would cause the di resin to deplete quickly and requires a degassing chamber to correct.

3. Improperly seated to membrane. If your tap is really only 27, but is bypassing the membrane then you are sending that 27 TDS water to the resin.

4. Improperly configured water lines. Occasionally people will accidently switch the product line and the waste line.

To test after the membrane, yes just disconnect the line to the di resin.
I'd use a glass container to collect the sample, rinse several time with rodi water, then collect the sample and take a reading.

I change sediment when I get a drop to 60psi, I usually got in 70-75psi.

I believe testing the waste water for chlorine is the best way to gauge carbon. I have the lamotte total chlorine/chlorine test strips( just bad about using them, lol). You can get them at bulkreefsupply for $11 or 12

No I did not use a handheld all I have is the inline one that came with the unit. But I'm gonna order one for sure now. I purchased the unit brand new through BRS and everything came already assembled. So I would assume that the water lines are installed correctly and that the resin would be packed correctly and that it's seated to the membrane correctly (or at least I hope so [emoji23]).

When the DI resin changes color, does it normally change all the bottom and work its way up? The reason I ask is if you look at my pic, the color change kind of swirls around the canister from bottom to top. It doesn't totally fill out the bottom. Is this an indication of channeling?

 

[Fudsey]

I have the 4 stage BRS unit with the TDS meter but it has 2 meters, in and out. My in is after membrane and out is after resin. My water pressure is 45-60 and have not needed to change any of the filters after almost a year except resin. Tap is 55 TDS and after membrane it is 3

 

[fishbox]

I have the 4 stage BRS unit with the TDS meter but it has 2 meters, in and out. My in is after membrane and out is after resin. My water pressure is 45-60 and have not needed to change any of the filters after almost a year except resin. Tap is 55 TDS and after membrane it is 3

Yes mine has the in and out switch. So my tap water is not 27 then because you're saying that the in is after the membrane. Glad you posted this

 

[Fudsey]

It is on my unit, check where the in tap is. I suspect it is after membrane and if it is coming out at 27, that would explain why your going through resin so fast. I have a handheld unit that I test my tap with. But if your tap is high TDS it would also explain the 27 after membrane

 

[cmcoker]

Yes mine has the in and out switch. So my tap water is not 27 then because you're saying that the in is after the membrane. Glad you posted this

Yeah if the "in" to di is 27 that's pretty high, I think. Did you let the system run for 10 minutes or so before taking that number?

The pattern in your resin is odd. Only one of the types of beads is dyed, there are anion and cation beads so they can pick up positive and negative charged molecules. It almost looks like the beads are stratisfied with all the dyed beads together.

 

[fishbox]

It is on my unit, check where the in tap is. I suspect it is after membrane and if it is coming out at 27, that would explain why your going through resin so fast. I have a handheld unit that I test my tap with. But if your tap is high TDS it would also explain the 27 after membrane

I'll definitely check the input in the morning

Yeah if the "in" to di is 27 that's pretty high, I think. Did you let the system run for 10 minutes or so before taking that number?

The pattern in your resin is odd. Only one of the types of beads is dyed, there are anion and cation beads so they can pick up positive and negative charged molecules. It almost looks like the beads are stratisfied with all the dyed beads together.

Yes I let it run for over 10 min. I know the BRS guys have been studying DI resin. Hopefully one of them could chime in about this odd pattern

 

[cmcoker]

I'll definitely check the input in the morning



Yes I let it run for over 10 min. I know the BRS guys have been studying DI resin. Hopefully one of them could chime in about this odd pattern

@Ryanbrs any input on the di resin appearance?