Exhausting DI Quickly!!!

phoenix001 · 09/21/2011, 09:25 AM

So, I just refilled my DI resin yesterday evening - I used the color changing kind this time as I wanted to see how quickly I used it up. I had just replaced it in early July, so that seemed fairly quick. Anyway, I replaced it last night and started filling my Brute 44 gallon. This morning, I noticed that a 1/4 of the DI resin at the top of the canister had turned brown!! I had nearly filled up the brute. I took some readings:

Tap water TDS = 408 (city water)
After RO TDS = 9
After DI TDS = 0

So, calcualting the membranes rejection rate:

(408-9)/408 * 100 gave me a rejection rate of 97.8

Does this mean my RO Membrane is bad? I replaced it back in early March 2010.

disc1 · 09/21/2011, 09:40 AM

You got 98% rejection, I think the membrane is OK.

phoenix001 · 09/21/2011, 09:53 AM

Quote:

Originally Posted by disc1

You got 98% rejection, I think the membrane is OK.

What other factors would cause me to use up the resin so quickly?

Chipie · 09/21/2011, 10:15 AM

I would like to know too. I have the same problem.

d0ughb0y · 09/21/2011, 11:54 AM

I'd say just go by the tds reading of your di output and not by the color. I can't tell by looking at the color through the translucent canister of my filter. are you able to see clearly the color? I think it is blue and turns to brown right?

the only time I had di exhaust quickly was when I was experimenting running the filter without an ro membrane, since my tap water tds is in the range of 20-50. bad idea.

phoenix001 · 09/21/2011, 01:15 PM

Quote:

Originally Posted by d0ughb0y

I'd say just go by the tds reading of your di output and not by the color. I can't tell by looking at the color through the translucent canister of my filter. are you able to see clearly the color? I think it is blue and turns to brown right?

the only time I had di exhaust quickly was when I was experimenting running the filter without an ro membrane, since my tap water tds is in the range of 20-50. bad idea.

Yeah, the resin turns from blue to brown - here is a pic form this morning. Again, I just changed the resin out yesterday evening. Pretty clear :-)

Rocdoc · 09/21/2011, 01:25 PM

I'm using the color-changing resin in a 20" (double-sized) BRS Spartan RO/DI unit. The resin changes color quickly. It is now almost all brown only a few hundred gallons later. TDS after the RO membrane is only 4 or 5. However, even though it's almost all brown, I'm still at 0ppm after the RO, so I just keep checking it when I'm filling the storage container.

96p993 · 09/21/2011, 01:54 PM

I agree with doughboy, just go by TDS after DI, it will tell you when it is really time to change

Buckeye Hydro · 09/21/2011, 04:47 PM

Looks to me like your color change is happenning at the top of the cartridge - which doesn't make sense becasue you should have "bottom-up" flow through the cartridge.

Generally when this happens it means that the DI resin wasn't packed tightly enough, and the mixed resin bed has fluidized and has at least started to separate.

Dump your resin out in a clean glass bowl, remix it, and put it back into the cartridge along with more resin so that the cartridge is packed very tightly.

Russ

Buckeye Hydro · 09/21/2011, 04:53 PM

The other problem of course is that you are right here in Cincinnati and are not using our resin!

(Our's turns from purple to tan)

Russ

phoenix001 · 09/21/2011, 05:19 PM

Quote:

Originally Posted by BuckeyeFS

The other problem of course is that you are right here in Cincinnati and are not using our resin!

(Our's turns from purple to tan)

Russ

Hey Russ. I normally get my resin from you but had a larger order with brs so just added it. Anyway, I used every bit if the resin that came in the refill, so there was nothing more I could of packed

. Anyway, looks like all I can do is use this one up and get another - would be curious to know if your refills include more resin than brs??

Ryan45 · 09/21/2011, 08:53 PM

As others have said, don't go by the color. I use color changing from BRS and it changes fast, still get 0 TDS on my meter.

Tigé21v · 09/21/2011, 09:06 PM

98% rejection rate is above average.
DI resin exposed to air (CO2) will will be degraded. Shouold be kept sealed.
Low RO ph will cause premature Di exhaustion.

souperman · 09/21/2011, 09:57 PM

I'm lucky to get 120G or so out of a single canister of resin at my place. We are on a well that reads 210-250TDS from the tap and I can only get down to 12-16 after my membrane. I have tried a booster pump, new membrane, and lots of flushing with no luck. I guess I am just blessed with crappy water. It pegs my nitrate test straight from the tap. I should be happy I can get 0 water form the filter at all I guess...

jimrawr · 09/21/2011, 10:13 PM

DI Resin will exhuast very fast if your water is low PH, happens a lot with well water. Consider yourself lucky, I have to replace my DI resin after making 40 gallons of water

Its beyond bad. I tried to have a secondary bucket where I would make RO water, then use an airstone and a powerhead to try and raise the PH. It really didnt help at all.

If anyone has a better way/method I am all ears

BonsaiNut · 09/22/2011, 07:17 AM

Just out of curiosity... what were you expecting? RO/DI resin only lasts for a few hundred gallons if you have crappy water (like most parts of the country). In Southern California it lasts about 400-600 gallons for me.

Buckeye Hydro · 09/22/2011, 09:03 AM

Quote:

Originally Posted by phoenix001

Hey Russ. I normally get my resin from you but had a larger order with brs so just added it. Anyway, I used every bit if the resin that came in the refill, so there was nothing more I could of packed

. Anyway, looks like all I can do is use this one up and get another - would be curious to know if your refills include more resin than brs??

I couldn't tell you, but I do know you'll have a tad left over in our resin bag after you fill the cartridge.

Russ

Garage1217 · 09/22/2011, 11:50 AM

In my experience and nothing against any vendors in this thread at all, I am just speaking from my experience. But in my area, we have insanely bad water (Coolidge Az) / Arizona in general. I am talking TDS can reach over 1000 in the summer and right now I am at 720 at my house. In short, spectrapure knows poor water and how to get the most out of DI life. If you have your system setup properly waste water wise, are using a quality membrane and getting good rejection, I cannot see why your DI stages are not lasting into at least 300-400 gallons. Even with my TDS as crazy as it is, I filled my 225 over the last few days including the sump, reactors and 20G top off tank and even with the rejection on my membrane at 97% right now, I am just barely seeing 1tds on the DI stage and 0TDS out of the silica buster stage. Now that is freaking impressive as I just made close to 300 gallons of RODI with nasty stinky water.

As I said, if you guys have set your systems up properly, give their maxcap DI stage and SB stage a try. Their Zeta Zorb .2 micron pre and carbon filters are also top notch. They also have special pricing for RC members.

Tigé21v · 09/22/2011, 04:44 PM

Quote:

Originally Posted by jimrawr

DI Resin will exhuast very fast if your water is low PH, happens a lot with well water. Consider yourself lucky, I have to replace my DI resin after making 40 gallons of water

Its beyond bad. I tried to have a secondary bucket where I would make RO water, then use an airstone and a powerhead to try and raise the PH. It really didnt help at all.

If anyone has a better way/method I am all ears

May want to look into giving this a try.

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

If you are burning through DI resin that fast, are you regenerating it?

http://reefkeeping.com/issues/2008-09/nftt/index.php

09/21/2011, 09:25 AM	#1
phoenix001 Premium Member Join Date: Jan 2004 Location: Cincinnati, Ohio Posts: 499	Exhausting DI Quickly!!! So, I just refilled my DI resin yesterday evening - I used the color changing kind this time as I wanted to see how quickly I used it up. I had just replaced it in early July, so that seemed fairly quick. Anyway, I replaced it last night and started filling my Brute 44 gallon. This morning, I noticed that a 1/4 of the DI resin at the top of the canister had turned brown!! I had nearly filled up the brute. I took some readings: Tap water TDS = 408 (city water) After RO TDS = 9 After DI TDS = 0 So, calcualting the membranes rejection rate: (408-9)/408 * 100 gave me a rejection rate of 97.8 Does this mean my RO Membrane is bad? I replaced it back in early March 2010.

09/21/2011, 09:40 AM	#2
disc1 -RT * ln(k) Join Date: Sep 2010 Location: Little Rock Posts: 9,705	You got 98% rejection, I think the membrane is OK. __________________ David Current Tank: Undergoing reconstruction...

09/21/2011, 10:15 AM	#4
Chipie Registered Member Join Date: May 2007 Location: Shippagan,New-Brunswick, Canada Posts: 1,116	I would like to know too. I have the same problem. __________________ Lobster fisherwoman. Current Tank Info: 90g rimless reef

09/21/2011, 10:13 PM	#15
jimrawr Registered Member Join Date: Dec 2006 Location: Palm Beach County, FL Posts: 1,887	DI Resin will exhuast very fast if your water is low PH, happens a lot with well water. Consider yourself lucky, I have to replace my DI resin after making 40 gallons of water Its beyond bad. I tried to have a secondary bucket where I would make RO water, then use an airstone and a powerhead to try and raise the PH. It really didnt help at all. If anyone has a better way/method I am all ears __________________ Tank Info: 75g, 40g Sump, AquaMaxx Skimmer, Two Tunze 6095, ATI 8x52", Bubble Magus Dosing Pump, Apex Controller, Tunze ATO.

09/22/2011, 07:17 AM	#16
BonsaiNut Premium Member Join Date: Mar 2002 Location: Orange County, CA Posts: 4,629	Just out of curiosity... what were you expecting? RO/DI resin only lasts for a few hundred gallons if you have crappy water (like most parts of the country). In Southern California it lasts about 400-600 gallons for me. __________________ "You are a very fine person, Mr. Baggins, and I am very fond of you; but you are only quite a little fellow in a wide world after all!" - The Hobbit; J. R. R. Tolkien

09/21/2011, 11:54 AM	#5
d0ughb0y Registered Member Join Date: Mar 2008 Location: sf bay area Posts: 5,165	I'd say just go by the tds reading of your di output and not by the color. I can't tell by looking at the color through the translucent canister of my filter. are you able to see clearly the color? I think it is blue and turns to brown right? the only time I had di exhaust quickly was when I was experimenting running the filter without an ro membrane, since my tap water tds is in the range of 20-50. bad idea.

09/21/2011, 01:25 PM	#7
Rocdoc Just not that bright Join Date: Jan 2011 Location: Tacoma, WA Posts: 152	I'm using the color-changing resin in a 20" (double-sized) BRS Spartan RO/DI unit. The resin changes color quickly. It is now almost all brown only a few hundred gallons later. TDS after the RO membrane is only 4 or 5. However, even though it's almost all brown, I'm still at 0ppm after the RO, so I just keep checking it when I'm filling the storage container.

09/21/2011, 01:54 PM	#8
96p993 Registered Member Join Date: Oct 2004 Location: Mckinney, Tx Posts: 1,130	I agree with doughboy, just go by TDS after DI, it will tell you when it is really time to change

09/21/2011, 04:47 PM	#9
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	Looks to me like your color change is happenning at the top of the cartridge - which doesn't make sense becasue you should have "bottom-up" flow through the cartridge. Generally when this happens it means that the DI resin wasn't packed tightly enough, and the mixed resin bed has fluidized and has at least started to separate. Dump your resin out in a clean glass bowl, remix it, and put it back into the cartridge along with more resin so that the cartridge is packed very tightly. Russ

09/21/2011, 04:53 PM	#10
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	The other problem of course is that you are right here in Cincinnati and are not using our resin! (Our's turns from purple to tan) Russ

09/21/2011, 08:53 PM	#12
Ryan45 Registered Member Join Date: Aug 2007 Posts: 97	As others have said, don't go by the color. I use color changing from BRS and it changes fast, still get 0 TDS on my meter.

09/21/2011, 09:06 PM	#13
Tigé21v Registered Member Join Date: Apr 2008 Location: St. Charles, Mo. Posts: 1,369	98% rejection rate is above average. DI resin exposed to air (CO2) will will be degraded. Shouold be kept sealed. Low RO ph will cause premature Di exhaustion.

09/21/2011, 09:57 PM	#14
souperman Registered Member Join Date: Dec 2010 Posts: 262	I'm lucky to get 120G or so out of a single canister of resin at my place. We are on a well that reads 210-250TDS from the tap and I can only get down to 12-16 after my membrane. I have tried a booster pump, new membrane, and lots of flushing with no luck. I guess I am just blessed with crappy water. It pegs my nitrate test straight from the tap. I should be happy I can get 0 water form the filter at all I guess...

09/22/2011, 11:50 AM	#18
Garage1217 GET OFF MY LAWN Join Date: Jul 2007 Location: Globally Posts: 5,863	In my experience and nothing against any vendors in this thread at all, I am just speaking from my experience. But in my area, we have insanely bad water (Coolidge Az) / Arizona in general. I am talking TDS can reach over 1000 in the summer and right now I am at 720 at my house. In short, spectrapure knows poor water and how to get the most out of DI life. If you have your system setup properly waste water wise, are using a quality membrane and getting good rejection, I cannot see why your DI stages are not lasting into at least 300-400 gallons. Even with my TDS as crazy as it is, I filled my 225 over the last few days including the sump, reactors and 20G top off tank and even with the rejection on my membrane at 97% right now, I am just barely seeing 1tds on the DI stage and 0TDS out of the silica buster stage. Now that is freaking impressive as I just made close to 300 gallons of RODI with nasty stinky water. As I said, if you guys have set your systems up properly, give their maxcap DI stage and SB stage a try. Their Zeta Zorb .2 micron pre and carbon filters are also top notch. They also have special pricing for RC members. __________________ No great genius has ever existed without some touch of madness ~ Aristotle If we knew what it was we were doing, it would not be called research, would it? ~ Albert Einstein I'm just as bent as ever. Hellishly so ~ Captain Jack Sparrow Current Tank Info: Systems and goodies by Lee-Mar / Coralvue / Neptune Systems / Jager / Spectrapure / Cree / Meanwell + more!

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
BRS RO/DI vs The Filter Guys vs Filter Direct????	Bigjav	Lighting, Filtration & Other Equipment	56	01/21/2012 11:04 AM
ro/di questions/problems	Arthur1	Lighting, Filtration & Other Equipment	8	10/08/2009 05:27 PM
RO/DI unit	blcketnies11	New to the Hobby	7	11/02/2008 01:46 AM
exhausting di resin very fast	rtbm	The Reef Chemistry Forum	14	07/17/2006 09:53 AM