TDS reading is terrible. What is wrong? 67 in & 529 out of RODI. HELP!!!

fe342185 · 10/12/2006, 07:54 AM

I replaced the 3 filters the other day. I'm not sure what the 4th cartridge is on top that has an arrow with the word flow on it but that was not replaced yet. Can that be the cause?

Thanks

Warnberg · 10/12/2006, 08:24 AM

What type of RO/DI system do you have? Usually the filter on top is the RO membrane. The RO membrane is usually good for several years, sometimes from the factory they do not get it in correctly or one of the filters you replaced is not in correctly and is letting water bypass the filter. Did you ever get a 0 TDS reading from your unit?

Not sure how the TDS can go up unless you are testing the waiste water.

bubbaOPPD · 10/12/2006, 08:25 AM

The one on top is the RO membrane, you might have one of the cartridges might be on wrong or you didn't let the water run out for a day or so to get the impurities out from manufacturing.

fe342185 · 10/12/2006, 02:56 PM

the RO is about 5 years old. There are 2 cartridges on top. I'm assuming the one directly above the 3 is the RO membrane since it had some valve on it to flush it out. How often am I suppose to flush the unit?

Should I get a new membrane or get a whole new RO unit? I hear the membranes are expensive.

Also another bad symptom is that the RO unit makes water very quickly. FIlled up my 32 gallon drum in about 4 hours. I think that was a little fast.

AZDesertRat · 10/12/2006, 04:17 PM

If its 5 years old its probably shot. Membranes normally last about 3 years if filters are changed and maintenance is done properly. It sounds like your membrane is delaminated and is coming apart to me. A 75 GPD Dow Filmtec membrane will cost you less than $50 shipped.

fe342185 · 10/12/2006, 05:48 PM

Thank you. I just ordered it.

Qwiv · 10/12/2006, 06:05 PM

I think the second chamber on top of our unit is a second carbon filter. These are often installed on systems that have a drinking water faucet with a storage container. I had one on mine and threw it away after it was all used up. After 5 years, that think is toast, should only last a few months. Get rid of it, you don't need it. You can tell if that is what it is as there is no way to open it. Kinda looks like this?
http://www.airwaterice.com/product/PR-D2586C
It is meant to make the water taste better to drink. That thing could be full of stuff and leeching into your water since it sounds like your membrane is toast as well.

Remember to change your filters. The sediment filter generaly protects the complete unit. The carbon protects the membrane from clorine, that will destroy it.

fe342185 · 10/12/2006, 08:17 PM

Qwiv - Thanks.. Thats exactly what was on the top. I will remove it as soon as I install the new membrane.

Thanks for the assistance everyone.

Last question is should I use straight tap water until the new membrane comes in or keep using the broken one with a TDS reading that is much higher than what was going in? Thanks

eclecticvibe · 10/12/2006, 08:30 PM

Don't use either if you don't have to. Chlorine from tap water is bad for your tank, plus you'll get phosphates and who knows what. The RO probably needs to be cleaned in hot soapy water and rinsed extremely well. All the cartridges should be replaced too. If you don't have a good carbon cartridge in front of the membrane, the chlorine will burn up and ruin the membrane. If you don't have a sediment cartridge the carbon can become clogged quickly and then it's mostly useless. Make sure you have the waste and product water lines correct. The unit shouldn't fill a tub that quickly. You should get 4 gallons of waste water for every gallong of good water. If not, you might need a new flow restrictor. It's best if you can use water between 70 and 80 degrees. You'll get more flow that way. Spectrapure has good instructions and diagrams for RO units on their website. Kent and others do as well I'm sure.

AZDesertRat · 10/12/2006, 08:43 PM

Buy distilled water as both will cause problems.

10/12/2006, 07:54 AM	#1
fe342185 Registered Member Join Date: Sep 2003 Location: Staten Island NY Posts: 641	TDS reading is terrible. What is wrong? 67 in & 529 out of RODI. HELP!!! I replaced the 3 filters the other day. I'm not sure what the 4th cartridge is on top that has an arrow with the word flow on it but that was not replaced yet. Can that be the cause? Thanks

10/12/2006, 06:05 PM	#7
Qwiv Persistant Perspective Join Date: Nov 2003 Location: Belmont, CA Posts: 2,168	I think the second chamber on top of our unit is a second carbon filter. These are often installed on systems that have a drinking water faucet with a storage container. I had one on mine and threw it away after it was all used up. After 5 years, that think is toast, should only last a few months. Get rid of it, you don't need it. You can tell if that is what it is as there is no way to open it. Kinda looks like this? http://www.airwaterice.com/product/PR-D2586C It is meant to make the water taste better to drink. That thing could be full of stuff and leeching into your water since it sounds like your membrane is toast as well. Remember to change your filters. The sediment filter generaly protects the complete unit. The carbon protects the membrane from clorine, that will destroy it. __________________ If I knew keeping fish would be so hard, I would of had kids by now. Current Tank Info: 50Cube + 250DD + Nano

10/12/2006, 08:30 PM	#9
eclecticvibe Premium Member Join Date: Jun 2004 Location: Indianapolis Posts: 583	Don't use either if you don't have to. Chlorine from tap water is bad for your tank, plus you'll get phosphates and who knows what. The RO probably needs to be cleaned in hot soapy water and rinsed extremely well. All the cartridges should be replaced too. If you don't have a good carbon cartridge in front of the membrane, the chlorine will burn up and ruin the membrane. If you don't have a sediment cartridge the carbon can become clogged quickly and then it's mostly useless. Make sure you have the waste and product water lines correct. The unit shouldn't fill a tub that quickly. You should get 4 gallons of waste water for every gallong of good water. If not, you might need a new flow restrictor. It's best if you can use water between 70 and 80 degrees. You'll get more flow that way. Spectrapure has good instructions and diagrams for RO units on their website. Kent and others do as well I'm sure. __________________ Jay Current Tank Info: Taking it all down.

10/12/2006, 08:24 AM	#2
Warnberg Registered Member Join Date: May 2004 Location: Tampa, Florida Posts: 1,366	What type of RO/DI system do you have? Usually the filter on top is the RO membrane. The RO membrane is usually good for several years, sometimes from the factory they do not get it in correctly or one of the filters you replaced is not in correctly and is letting water bypass the filter. Did you ever get a 0 TDS reading from your unit? Not sure how the TDS can go up unless you are testing the waiste water.

10/12/2006, 08:25 AM	#3
bubbaOPPD Moved On Join Date: Oct 2005 Location: Omaha, Nebraska Posts: 416	The one on top is the RO membrane, you might have one of the cartridges might be on wrong or you didn't let the water run out for a day or so to get the impurities out from manufacturing.

10/12/2006, 02:56 PM	#4
fe342185 Registered Member Join Date: Sep 2003 Location: Staten Island NY Posts: 641	the RO is about 5 years old. There are 2 cartridges on top. I'm assuming the one directly above the 3 is the RO membrane since it had some valve on it to flush it out. How often am I suppose to flush the unit? Should I get a new membrane or get a whole new RO unit? I hear the membranes are expensive. Also another bad symptom is that the RO unit makes water very quickly. FIlled up my 32 gallon drum in about 4 hours. I think that was a little fast.

10/12/2006, 04:17 PM	#5
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	If its 5 years old its probably shot. Membranes normally last about 3 years if filters are changed and maintenance is done properly. It sounds like your membrane is delaminated and is coming apart to me. A 75 GPD Dow Filmtec membrane will cost you less than $50 shipped.

10/12/2006, 05:48 PM	#6
fe342185 Registered Member Join Date: Sep 2003 Location: Staten Island NY Posts: 641	Thank you. I just ordered it.

10/12/2006, 08:17 PM	#8
fe342185 Registered Member Join Date: Sep 2003 Location: Staten Island NY Posts: 641	Qwiv - Thanks.. Thats exactly what was on the top. I will remove it as soon as I install the new membrane. Thanks for the assistance everyone. Last question is should I use straight tap water until the new membrane comes in or keep using the broken one with a TDS reading that is much higher than what was going in? Thanks

10/12/2006, 08:43 PM	#10
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Buy distilled water as both will cause problems.