Membrane ?

hawkfish21 · 08/09/2006, 05:32 PM

I was just wondering how often everyone changes their membrane in their RO/DI? Thanks.

55semireef · 08/09/2006, 06:11 PM

What kind do you have?

AZDesertRat · 08/09/2006, 06:11 PM

If you are using good quality pre and carbon filters and changing them every 6 months as recommended a membrane should last 3 to 4 years. I have had 2 go 3+ years now and am over 2 years on the current one with no measureable drop in water quality or quantity and thats with high TDS (600+) Phoenix water.

hawkfish21 · 08/09/2006, 06:29 PM

It's a Kent Maxxima Hi-S. I actually change my sediment & carbon filters every three months. The membrane is less than a year old. I am having a small Cyano outbreak and am eliminating every factor. It all started when I switched from Kent to IO. I recently switched back to Kent. Things are looking better, but how many more large water changes must I do? IMO, IO is crap.

AZDesertRat · 08/09/2006, 06:38 PM

If you think it might be your RO unit you need a good quality TDS meter to troubleshoot it. I highly recommend the new COM-100 meter from HM Digital. Lots of vendors are cvarrying it now and it blows every other handheld meter out of the water as far as accuracy and sensitivity, it will accurately measure down in the megaohm range which no other meter will do.
If you have DI how are you determining the condition of your resin and how often and at what level do you change it?

hawkfish21 · 08/09/2006, 06:41 PM

The resin turns orange when exhausted. I have a TDS meter and it constantly reads 0.

AZDesertRat · 08/09/2006, 08:37 PM

Do not rely on color changing resin to tell you anything. It is very unrelaible and usually by the time it turns its too late.
You say you always get 0 on your TDS meter, what are your tap water and RO only without DI readings and how efficient is your RO membrane ? How good is your TDS meter and has it been kept clean and calibrated? We all assume lots of things that may not necessarily be true.

hawkfish21 · 08/09/2006, 08:52 PM

Tap coming in is 180. I have two different TDS meters and both read 0.

AZDesertRat · 08/09/2006, 09:24 PM

What about RO only? Thats the number you need to tell how efficient your membrane is.

08/09/2006, 05:32 PM	#1
hawkfish21 Registered Member Join Date: Dec 2002 Location: Thornton, Colorado Posts: 1,968	Membrane ? I was just wondering how often everyone changes their membrane in their RO/DI? Thanks.

08/09/2006, 06:11 PM	#2
55semireef Moved On Join Date: May 2006 Location: Orlando, FL Posts: 5,322	What kind do you have?

08/09/2006, 06:11 PM	#3
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	If you are using good quality pre and carbon filters and changing them every 6 months as recommended a membrane should last 3 to 4 years. I have had 2 go 3+ years now and am over 2 years on the current one with no measureable drop in water quality or quantity and thats with high TDS (600+) Phoenix water.

08/09/2006, 06:29 PM	#4
hawkfish21 Registered Member Join Date: Dec 2002 Location: Thornton, Colorado Posts: 1,968	It's a Kent Maxxima Hi-S. I actually change my sediment & carbon filters every three months. The membrane is less than a year old. I am having a small Cyano outbreak and am eliminating every factor. It all started when I switched from Kent to IO. I recently switched back to Kent. Things are looking better, but how many more large water changes must I do? IMO, IO is crap.

08/09/2006, 06:38 PM	#5
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	If you think it might be your RO unit you need a good quality TDS meter to troubleshoot it. I highly recommend the new COM-100 meter from HM Digital. Lots of vendors are cvarrying it now and it blows every other handheld meter out of the water as far as accuracy and sensitivity, it will accurately measure down in the megaohm range which no other meter will do. If you have DI how are you determining the condition of your resin and how often and at what level do you change it?

08/09/2006, 06:41 PM	#6
hawkfish21 Registered Member Join Date: Dec 2002 Location: Thornton, Colorado Posts: 1,968	The resin turns orange when exhausted. I have a TDS meter and it constantly reads 0.

08/09/2006, 08:37 PM	#7
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Do not rely on color changing resin to tell you anything. It is very unrelaible and usually by the time it turns its too late. You say you always get 0 on your TDS meter, what are your tap water and RO only without DI readings and how efficient is your RO membrane ? How good is your TDS meter and has it been kept clean and calibrated? We all assume lots of things that may not necessarily be true.

08/09/2006, 08:52 PM	#8
hawkfish21 Registered Member Join Date: Dec 2002 Location: Thornton, Colorado Posts: 1,968	Tap coming in is 180. I have two different TDS meters and both read 0.

08/09/2006, 09:24 PM	#9
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	What about RO only? Thats the number you need to tell how efficient your membrane is.