Ro/di help!!!

fishman1234 · 07/24/2012, 04:37 PM

The water that is coming out of my RO unit is reading a 008 on the tds meter. The tap comes out @ 250. Does the RO water have to 100% be 000 reading on the tds?

spinoleo · 07/24/2012, 05:01 PM

is this a new unit?

Capt_Cully · 07/24/2012, 05:18 PM

Do you have DI resin canisters after the RO unit?

fishman1234 · 07/24/2012, 06:56 PM

the resin is the last thing on and no it is not a new unit

spinoleo · 07/24/2012, 07:18 PM

do you have a reading before it gets to the di chamber

fishman1234 · 07/24/2012, 07:21 PM

no..........???

88rxna · 07/24/2012, 07:28 PM

I just had the same problem. I took the cap off of the membrane and twisted the membrane itself to make sure it was seated. turned it back on and im back to 000 TDS.
Not saying it will fix your problem but it may just help.
I read sometimes they may not fully seat and leak.

fishman1234 · 07/24/2012, 07:34 PM

membrane is in there tight. the order goes sediment catcher, carbon, membrane then di.

DEEP BLUE SIX · 07/24/2012, 09:10 PM

How many TDS meter lines do you have going in the whole system?
1 IN and 1 Out sections?

Try un plugging them and re inserting.
Also, try re setting the TDS meter screen it self, Purging out the unit, and letting some run out the good water line for awhile. See if it eventually starts going down... to 0.
Might happen to take a while. Several minutes. If not, then move on to checking at each point (if possible) with the meter. Or you may need to go to changing the filters out if nothing else. How old? Mine actually last a LONG time.

How old is the membrane?

As others have said, check the DI resin chamber too.- how long used? perhaps spent- leaching stuff back into water? If nothing else.. Try taking it off line. Save resin but empty chamber and run without DI temporarily. See what you get for a reading then.

You could be at a 1 or 2 and be ok I guess according to other people. But I've never settled for nothing less than 0 myself.

E_rock · 07/24/2012, 09:19 PM

+1.

fishman1234 · 07/25/2012, 08:20 AM

All are new except for membrane

SkiFletch · 07/25/2012, 11:28 AM

Take a sample of the water between the RO membrane and the DI resin. 250 is a lot of input and if you had a 100gpd membrane, 8ppm down from 250 would be pretty normal, just indicating a membrane in need of a little flush, and a saturated DI resin. If it's 8ppm before the DI (or maybe even something like 10) that would be my guess.

tmz · 07/25/2012, 12:00 PM

Post tds needs to be zero. The resins when exhuasted release ammonia, PO4 and other troublesome solids first as more highly charged ions bump them out. So even .01 tds from di could be a problem when it wouldn't be singnificant for just ro.
Test the membrane output with a tds meter. Typically, membranes have a rejction rate of 95% to 98%,so depending on your membrane's rating .I'd expect tds from the membrane to be 5 to 13 tds on an input of 250tds. If it's higher the resin will exhaust quickly.

Personlly, I use two di canisters with a tds meter in between them . When the output of the first one in line shows above 0, I change the resin in it and rotate it to second position. This insures 0 tds and eliminates the guesswork as to whether resin is exhausted; color changing is not especially helpful in gauging exhaustion ,ime. With two canisters and the tds meter in between I not only get 0 tds all the time but use teh resin more efficiently because I don't change it prematurely.

Also test after water is flowing for 30 seconds or so to get a fair reading to avoid reading the higher tds( tds creep) that can occur on start up. The in line meters are most effective when water is flowing.

07/24/2012, 04:37 PM	#1
fishman1234 Registered Member Join Date: Jun 2012 Location: West Seneca NY Posts: 189	Ro/di help!!! The water that is coming out of my RO unit is reading a 008 on the tds meter. The tap comes out @ 250. Does the RO water have to 100% be 000 reading on the tds?

07/24/2012, 05:01 PM	#2
spinoleo Registered Member Join Date: Jul 2007 Location: orchard park, NY Posts: 785	is this a new unit? __________________ I used to be a human lawn dart Current Tank Info: 120rr, octo nw-200 ,2x radions basement sump,mp40

07/24/2012, 05:18 PM	#3
Capt_Cully Registered Member Join Date: Sep 2004 Location: Syracuse, NY Posts: 11,548	Do you have DI resin canisters after the RO unit? __________________ ....love to prove that, wouldn't ya. Get your name in The National Geographic.... Current Tank Info: 200DD SPS dominated mixed reef

07/24/2012, 07:18 PM	#5
spinoleo Registered Member Join Date: Jul 2007 Location: orchard park, NY Posts: 785	do you have a reading before it gets to the di chamber __________________ I used to be a human lawn dart Current Tank Info: 120rr, octo nw-200 ,2x radions basement sump,mp40

07/24/2012, 07:28 PM	#7
88rxna Registered Member Join Date: Jun 2012 Location: ludlow,PA Posts: 343	I just had the same problem. I took the cap off of the membrane and twisted the membrane itself to make sure it was seated. turned it back on and im back to 000 TDS. Not saying it will fix your problem but it may just help. I read sometimes they may not fully seat and leak. __________________ 90 gallon display, CSC bean animal overflow 30 gallon sump (in basement) SWC 160 skimmer reeflow dart external pump reefkeeper lite

07/24/2012, 06:56 PM	#4
fishman1234 Registered Member Join Date: Jun 2012 Location: West Seneca NY Posts: 189	the resin is the last thing on and no it is not a new unit

07/24/2012, 07:21 PM	#6
fishman1234 Registered Member Join Date: Jun 2012 Location: West Seneca NY Posts: 189	no..........???

07/24/2012, 07:34 PM	#8
fishman1234 Registered Member Join Date: Jun 2012 Location: West Seneca NY Posts: 189	membrane is in there tight. the order goes sediment catcher, carbon, membrane then di.

07/24/2012, 09:10 PM	#9
DEEP BLUE SIX Registered Member Join Date: Nov 2009 Location: Between Rochester & Buffalo Posts: 527	How many TDS meter lines do you have going in the whole system? 1 IN and 1 Out sections? Try un plugging them and re inserting. Also, try re setting the TDS meter screen it self, Purging out the unit, and letting some run out the good water line for awhile. See if it eventually starts going down... to 0. Might happen to take a while. Several minutes. If not, then move on to checking at each point (if possible) with the meter. Or you may need to go to changing the filters out if nothing else. How old? Mine actually last a LONG time. How old is the membrane? As others have said, check the DI resin chamber too.- how long used? perhaps spent- leaching stuff back into water? If nothing else.. Try taking it off line. Save resin but empty chamber and run without DI temporarily. See what you get for a reading then. You could be at a 1 or 2 and be ok I guess according to other people. But I've never settled for nothing less than 0 myself. __________________ The sea is everything. It covers seven tenths of the terrestrial globe. Its breath is pure and healthy. It is an immense desert, where man is never lonely, for he feels life stirring on all sides. - Jules Verne You don't keep fish, you keep Water - David Saxby OCR- many of us have it. (Obsessive Compulsive Reef Disorder) Current Tank Info: Back in: Currently a 1 year new Custom center end RR 90 gallon Penninsula Reef w/ 2x250watt Halides 14K, Actinic T5's, Skimmer, GFO reactor, UV, 40 gal Sump, Mag return, ATO w/saturated Kalk RO, 2 part suppl. dosing pumps(2), LPS/SPS mix &FISH Last edited by DEEP BLUE SIX; 07/24/2012 at 09:16 PM.

07/24/2012, 09:19 PM	#10
E_rock Registered Member Join Date: Aug 2011 Location: West Seneca, NY Posts: 263	+1. __________________ -Eric Current Tank Info: 90 gallon reef

07/25/2012, 08:20 AM	#11
fishman1234 Registered Member Join Date: Jun 2012 Location: West Seneca NY Posts: 189	All are new except for membrane

07/25/2012, 11:28 AM	#12
SkiFletch Registered Member Join Date: Apr 2006 Location: N Buffalo, NY Posts: 3,638	Take a sample of the water between the RO membrane and the DI resin. 250 is a lot of input and if you had a 100gpd membrane, 8ppm down from 250 would be pretty normal, just indicating a membrane in need of a little flush, and a saturated DI resin. If it's 8ppm before the DI (or maybe even something like 10) that would be my guess. __________________ You will miss 100% of the shots you dont take. Dare to dream Mike, aka Fletch Current Tank Info: 65 gallon reef

07/25/2012, 12:00 PM	#13
tmz ReefKeeping Mag staff Join Date: Apr 2006 Location: West Seneca NY Posts: 19,764	Post tds needs to be zero. The resins when exhuasted release ammonia, PO4 and other troublesome solids first as more highly charged ions bump them out. So even .01 tds from di could be a problem when it wouldn't be singnificant for just ro. Test the membrane output with a tds meter. Typically, membranes have a rejction rate of 95% to 98%,so depending on your membrane's rating .I'd expect tds from the membrane to be 5 to 13 tds on an input of 250tds. If it's higher the resin will exhaust quickly. Personlly, I use two di canisters with a tds meter in between them . When the output of the first one in line shows above 0, I change the resin in it and rotate it to second position. This insures 0 tds and eliminates the guesswork as to whether resin is exhausted; color changing is not especially helpful in gauging exhaustion ,ime. With two canisters and the tds meter in between I not only get 0 tds all the time but use teh resin more efficiently because I don't change it prematurely. Also test after water is flowing for 30 seconds or so to get a fair reading to avoid reading the higher tds( tds creep) that can occur on start up. The in line meters are most effective when water is flowing. __________________ Tom Current Tank Info: Tank of the Month , November 2011 : 600gal integrated system: 3 display tanks (120 g, 90g, 89g),several frag/grow out tanks, macroalgae refugia, cryptic zones. 40+ fish, seahorses, sps,lps,leathers, zoanthidae and non photosynthetic corals.