Slow Ro/DI

philosophile · 12/16/2011, 09:38 AM

So I have a RODI system from BRS, and its about a year old now. It used to make 5 gallons of water in about 85 minutes. Now it takes about 2 + hours to make water. Is it just because the water is colder, or is it because the membrane is clogged up? Is there anything I can do to speed up the RO membrane? I've heard of flushing it, but I'm not sure how to do that.

LukeGI · 12/16/2011, 09:46 AM

As to flushing the RO membrane....BRS's website has an instructional video on how to use their flush kit...it should help.
http://www.bulkreefsupply.com/store/...flush-kit.html

As for it slowing down, this could be a couple things. Do you have a pressure gauge on the unit? Is the incoming pressure lower than it used to be?
Do you have a TDS meter on the unit? Are you still getting 0 TDS out of the unit? If the housings are clear, do the pre-filters appear clogged or full? It might be time to change those out anyway.

philosophile · 12/16/2011, 09:53 AM

No I don't have a pressure gauge on the system, but I'm in the city, so unless the municipal water system has changed pressure, there shouldn't be any pressure changes.

I recently replaced the carbon and sediment filters and the DI. I think in August. Still getting zero TDS, and water from the RO system is at 6TDS... Water out of the tap is something like 230.

LukeGI · 12/16/2011, 10:00 AM

Has anything been changed in your system? valves replaced, other things replaced? anything that could have been dislodged and be clogging things anywhere? Also...you might want to find out just what pressure you have going into the ro system to know if the issue is your water pressure in the house or the ro system itself

frankiep · 12/16/2011, 10:16 AM

i would say cold water

Buckeye Hydro · 12/16/2011, 10:38 AM

We have a calculator on our site that let's you plug in water temperature and water pressure and see what you should be getting out of your membrane.

For instance:
75 gpd membrane, 50 psi, 65 degree water: 59 gpd
75 gpd membrane, 50 psi, 52 degree water: 46 gpd

Russ

Sugar Magnolia · 12/16/2011, 10:43 AM

Quote:

Originally Posted by BuckeyeFS

We have a calculator on our site that let's you plug in water temperature and water pressure and see what you should be getting out of your membrane.

For instance:
75 gpd membrane, 50 psi, 65 degree water: 59 gpd
75 gpd membrane, 50 psi, 52 degree water: 46 gpd

Russ

Good to know Russ. Mine's running on the cold line and has always run slow from the beginning. I get about 3/gph on my 75 gpd unit.

Buckeye Hydro · 12/16/2011, 11:17 AM

3 gph = 72 gpd, so that's pretty close to what the factory says you'll get if you run it at 50 psi with 77 degree water.

philosophile · 12/16/2011, 02:29 PM

yeah, okay, that sounds about right, in terms of slow down. Its probably just cold water. I'm usually making water in the morning, when I'm doing my maintenance on the tank. So the water is pretty cold still from the night before. Thanks!

12/16/2011, 09:38 AM	#1
philosophile Registered Member Join Date: Jul 2010 Location: San Jose, CA Posts: 1,149	Slow Ro/DI So I have a RODI system from BRS, and its about a year old now. It used to make 5 gallons of water in about 85 minutes. Now it takes about 2 + hours to make water. Is it just because the water is colder, or is it because the membrane is clogged up? Is there anything I can do to speed up the RO membrane? I've heard of flushing it, but I'm not sure how to do that. __________________ 90 gallon mixed reef XPS1000SSS skimmer, 2 radions gen 1, tunze osmolator w/ kalk dispenser, 70 lbs pukani, mp40w x2; 1 tomini, 1 clown 2 mandarins. Vinegar dosing, and micro bubble scrubbing.

12/16/2011, 09:46 AM	#2
LukeGI Registered Member Join Date: Apr 2010 Location: Kansas City, MO Posts: 240	As to flushing the RO membrane....BRS's website has an instructional video on how to use their flush kit...it should help. http://www.bulkreefsupply.com/store/...flush-kit.html As for it slowing down, this could be a couple things. Do you have a pressure gauge on the unit? Is the incoming pressure lower than it used to be? Do you have a TDS meter on the unit? Are you still getting 0 TDS out of the unit? If the housings are clear, do the pre-filters appear clogged or full? It might be time to change those out anyway. __________________ "Dream no small dreams. They have no power to stir the souls of men." - Victor Hugo Current Tank Info: 180g Mixed Reef, 40B sump, LED lights

12/16/2011, 09:53 AM	#3
philosophile Registered Member Join Date: Jul 2010 Location: San Jose, CA Posts: 1,149	No I don't have a pressure gauge on the system, but I'm in the city, so unless the municipal water system has changed pressure, there shouldn't be any pressure changes. I recently replaced the carbon and sediment filters and the DI. I think in August. Still getting zero TDS, and water from the RO system is at 6TDS... Water out of the tap is something like 230. __________________ 90 gallon mixed reef XPS1000SSS skimmer, 2 radions gen 1, tunze osmolator w/ kalk dispenser, 70 lbs pukani, mp40w x2; 1 tomini, 1 clown 2 mandarins. Vinegar dosing, and micro bubble scrubbing.

12/16/2011, 10:00 AM	#4
LukeGI Registered Member Join Date: Apr 2010 Location: Kansas City, MO Posts: 240	Has anything been changed in your system? valves replaced, other things replaced? anything that could have been dislodged and be clogging things anywhere? Also...you might want to find out just what pressure you have going into the ro system to know if the issue is your water pressure in the house or the ro system itself __________________ "Dream no small dreams. They have no power to stir the souls of men." - Victor Hugo Current Tank Info: 180g Mixed Reef, 40B sump, LED lights

12/16/2011, 02:29 PM	#9
philosophile Registered Member Join Date: Jul 2010 Location: San Jose, CA Posts: 1,149	yeah, okay, that sounds about right, in terms of slow down. Its probably just cold water. I'm usually making water in the morning, when I'm doing my maintenance on the tank. So the water is pretty cold still from the night before. Thanks! __________________ 90 gallon mixed reef XPS1000SSS skimmer, 2 radions gen 1, tunze osmolator w/ kalk dispenser, 70 lbs pukani, mp40w x2; 1 tomini, 1 clown 2 mandarins. Vinegar dosing, and micro bubble scrubbing.

12/16/2011, 10:16 AM	#5
frankiep Registered Member Join Date: Jun 2011 Posts: 35	i would say cold water

12/16/2011, 10:38 AM	#6
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	We have a calculator on our site that let's you plug in water temperature and water pressure and see what you should be getting out of your membrane. For instance: 75 gpd membrane, 50 psi, 65 degree water: 59 gpd 75 gpd membrane, 50 psi, 52 degree water: 46 gpd Russ

12/16/2011, 11:17 AM	#8
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	3 gph = 72 gpd, so that's pretty close to what the factory says you'll get if you run it at 50 psi with 77 degree water.

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