Adding DI stage to home RO system

pf1130 · 04/21/2008, 12:30 AM

Lately I have been buying my RO/DI water from the LFS. At home I have a GE smartwater RO drinking water system that I was originally using as my source for FW. I stopped using it because it seems to contain chloramine (water tests shows small levels of ammonia). My question is can I simply add a DI stage to this unit and use the water it produces for my reef? Is there any limitation or shortcoming of this system versus one of the RO/DI units "designed" for reef use? Or do I really need to spend the cash on a RO/DI unit?

pf1130 · 04/21/2008, 06:42 PM

anyone?

Roland Jacques · 04/21/2008, 07:13 PM

Yes, you can add a DI and get great quality water

Do you have a link to the GE RO.

pf1130 · 04/21/2008, 08:50 PM

Thanks for your response, just wanted to make sure I wasn't wasting money by trying to save some.

http://products.geappliances.com/Pro...&SKU=GXRM10GBL

Thats the owners manual. Should I post back with TDS reading after the RO unit when I get my TDS meter in?

AZDesertRat · 04/22/2008, 09:59 AM

I used a modified Watts Premier Costco drinking water system for years. Over time I upgraded from the 25 GPD to a 75 GPD membrane, replaced the standard filters with higher quality prefilter and carbons and added a final DI stage. It ended up costing more in the long run than if I had bought the reef system to begin with but this was back in 1992 when there weren't so many systems available either.
Once you get your TDS meter test the tap water TDS and RO TDS to see how efficient your system is. If its in the 95-98% rejection or removal ranges its probably a wise investment. If the RO is not real efficient then money might be better spent on a new $150-169 reef quality unit since DI replacements will add up quickly.

pf1130 · 04/24/2008, 08:49 PM

Just got my TDS meter in today. My tap water is at 242ppm, and the RO water from the GE unit is 18ppm. For references sake my LFS's RODI is at 3ppm. All filters as well as the RO membrane on the GE unit are brand new. Is this performance acceptable enough to add a DI stage? I don't want to burn through too much DI resin, but dont know whats a good number after the RO stage.

AZDesertRat · 04/24/2008, 10:01 PM

Its worth a try. Depending on CO2 levels you should get anywhere between 100 and 400 gallons or so per cartridge I would imagine. Probably on the mid to higher end.
My water has pretty high CO2 and I was getting 150 gallons per DI cartridge with a RO only TDS between 13 and 15.

pf1130 · 04/24/2008, 10:04 PM

Cool, Thanks for the reply. What should I look for in a DI stage? Or better yet can you recommend a quality, well priced one?

AZDesertRat · 04/24/2008, 10:10 PM

Look for a full sized 10" vertical canister type which can hold a refillable 20 oz cartridge. Most if not all the RC Sponsors who deal in RO/DI systems will have them.
If maximum DI life and highest quality water are of concern look at the MaxCap dual add on from www.spectrapure.com . It will last at least 3.5x longer than any other DI resin available and probably longerthan that. I am consistently getting better than 5 times the DI resin life than I was getting with any other resin I tried. They custom blend all their resins after tremendous amounts of research and development and it pays off.

04/21/2008, 12:30 AM	#1
pf1130 Registered Member Join Date: Jan 2008 Location: Miami, Florida Posts: 100	Adding DI stage to home RO system Lately I have been buying my RO/DI water from the LFS. At home I have a GE smartwater RO drinking water system that I was originally using as my source for FW. I stopped using it because it seems to contain chloramine (water tests shows small levels of ammonia). My question is can I simply add a DI stage to this unit and use the water it produces for my reef? Is there any limitation or shortcoming of this system versus one of the RO/DI units "designed" for reef use? Or do I really need to spend the cash on a RO/DI unit?

04/21/2008, 07:13 PM	#3
Roland Jacques Premium Member Join Date: Mar 2003 Location: Atlanta GA Posts: 2,848	Yes, you can add a DI and get great quality water Do you have a link to the GE RO. __________________ Roland

04/21/2008, 06:42 PM	#2
pf1130 Registered Member Join Date: Jan 2008 Location: Miami, Florida Posts: 100	anyone?

04/21/2008, 08:50 PM	#4
pf1130 Registered Member Join Date: Jan 2008 Location: Miami, Florida Posts: 100	Thanks for your response, just wanted to make sure I wasn't wasting money by trying to save some. http://products.geappliances.com/Pro...&SKU=GXRM10GBL Thats the owners manual. Should I post back with TDS reading after the RO unit when I get my TDS meter in?

04/22/2008, 09:59 AM	#5
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	I used a modified Watts Premier Costco drinking water system for years. Over time I upgraded from the 25 GPD to a 75 GPD membrane, replaced the standard filters with higher quality prefilter and carbons and added a final DI stage. It ended up costing more in the long run than if I had bought the reef system to begin with but this was back in 1992 when there weren't so many systems available either. Once you get your TDS meter test the tap water TDS and RO TDS to see how efficient your system is. If its in the 95-98% rejection or removal ranges its probably a wise investment. If the RO is not real efficient then money might be better spent on a new $150-169 reef quality unit since DI replacements will add up quickly.

04/24/2008, 08:49 PM	#6
pf1130 Registered Member Join Date: Jan 2008 Location: Miami, Florida Posts: 100	Just got my TDS meter in today. My tap water is at 242ppm, and the RO water from the GE unit is 18ppm. For references sake my LFS's RODI is at 3ppm. All filters as well as the RO membrane on the GE unit are brand new. Is this performance acceptable enough to add a DI stage? I don't want to burn through too much DI resin, but dont know whats a good number after the RO stage.

04/24/2008, 10:01 PM	#7
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Its worth a try. Depending on CO2 levels you should get anywhere between 100 and 400 gallons or so per cartridge I would imagine. Probably on the mid to higher end. My water has pretty high CO2 and I was getting 150 gallons per DI cartridge with a RO only TDS between 13 and 15.

04/24/2008, 10:04 PM	#8
pf1130 Registered Member Join Date: Jan 2008 Location: Miami, Florida Posts: 100	Cool, Thanks for the reply. What should I look for in a DI stage? Or better yet can you recommend a quality, well priced one?

04/24/2008, 10:10 PM	#9
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Look for a full sized 10" vertical canister type which can hold a refillable 20 oz cartridge. Most if not all the RC Sponsors who deal in RO/DI systems will have them. If maximum DI life and highest quality water are of concern look at the MaxCap dual add on from www.spectrapure.com . It will last at least 3.5x longer than any other DI resin available and probably longerthan that. I am consistently getting better than 5 times the DI resin life than I was getting with any other resin I tried. They custom blend all their resins after tremendous amounts of research and development and it pays off.