Can water pressure really affect RODI product water quality that much?

Michaelinpr · 10/30/2014, 02:40 PM

I just replaced my RO membrane, Di catridge, sediment filter and carbon filter. I do not have a tds meter but i decided to test for DKH and Calcium which I have test kits for.

DKH was around 1.5 and calcium was still 60 ppm. Tap water is 5 DKH and 85-90 ppm calcium.

My water pressure here is terrible. 35 psi last time I checked. And can be lower dependi g on the time and day of the week.

Can the low water pressure affect the output purity that much?

Vinny Kreyling · 10/30/2014, 03:08 PM

Don't know about purity but performance takes a dive with low pressure.

Michaelinpr · 10/30/2014, 03:40 PM

My production isn't too bad. I measured the other day and was getting just under 50 gpd from a spectrapure 60. This was measured after doing the appropriate cut to length of the flow restrictor.

CoralNerd · 10/30/2014, 03:45 PM

I had the opposite problem, my pressure was so high it blew through the DI and didn't filter it at all.

azjohnny · 10/30/2014, 07:10 PM

Pressure and temp is what will effect a RO/DI filter. I have 100psi and it almost doubles the water production and I get a little bit lower TDS after the membrane

The warmer the water is the more water will get produced but will get slightly higher TDS

CoralNerd- What brand of DI are you using?

DiscusHeckel · 10/31/2014, 08:14 AM

My RO membrane's specification indicates that the optimum pressure is 50 psi. If you get more than that I can only assume that the purification will be less than ideal.

azjohnny · 10/31/2014, 08:43 AM

Quote:

Originally Posted by DiscusHeckel

My RO membrane's specification indicates that the optimum pressure is 50 psi. If you get more than that I can only assume that the purification will be less than ideal.

That is the industry standard for the membranes ratings. the more pressure you give the membrane the more efficient it will be, you just don't want to give it so much where you crack a housing or a fitting leaks

10/30/2014, 02:40 PM	#1
Michaelinpr Registered Member Join Date: Oct 2014 Location: Puerto Rico Posts: 65	Can water pressure really affect RODI product water quality that much? I just replaced my RO membrane, Di catridge, sediment filter and carbon filter. I do not have a tds meter but i decided to test for DKH and Calcium which I have test kits for. DKH was around 1.5 and calcium was still 60 ppm. Tap water is 5 DKH and 85-90 ppm calcium. My water pressure here is terrible. 35 psi last time I checked. And can be lower dependi g on the time and day of the week. Can the low water pressure affect the output purity that much?

10/31/2014, 08:14 AM	#6
DiscusHeckel Acropora Gardener Join Date: Dec 2009 Location: Sheffield, UK Posts: 2,780	My RO membrane's specification indicates that the optimum pressure is 50 psi. If you get more than that I can only assume that the purification will be less than ideal. __________________ Featured Tank OCT 2016 \| "Reef Hobbyist Magazine" TOTM OCT 2016 \| "Ultimate Reef", UK FB \| "/troutsReefTank/" 65G SPS Reef- ATI 8 X 39W PM; TM [Bacto-Balance A-; Reef Actif; Nitribiotic; Iodine]

10/30/2014, 03:08 PM	#2
Vinny Kreyling Registered Member Join Date: Nov 2002 Location: Miller Place, NY Posts: 7,206	Don't know about purity but performance takes a dive with low pressure.

10/30/2014, 03:40 PM	#3
Michaelinpr Registered Member Join Date: Oct 2014 Location: Puerto Rico Posts: 65	My production isn't too bad. I measured the other day and was getting just under 50 gpd from a spectrapure 60. This was measured after doing the appropriate cut to length of the flow restrictor.

10/30/2014, 03:45 PM	#4
CoralNerd Registered Member Join Date: May 2014 Location: 92833 Posts: 1,099	I had the opposite problem, my pressure was so high it blew through the DI and didn't filter it at all.

10/30/2014, 07:10 PM	#5
azjohnny Registered Member Join Date: Apr 2012 Location: Gold Canyon Posts: 2,914	Pressure and temp is what will effect a RO/DI filter. I have 100psi and it almost doubles the water production and I get a little bit lower TDS after the membrane The warmer the water is the more water will get produced but will get slightly higher TDS CoralNerd- What brand of DI are you using?