rodi water storage

joekool · Jan 13, 2014

Has anyone tested with other tests other than hanna checker.
In any case what is the funky cat urine smell they get in them after storing water in them. Others have reported this same thing.

mcarroll · Jan 14, 2014

RODI water is the ultimate solvent - especially in an ultra-pure form lie RODI-processed. It's like a sponge and will absorb anything - even from the air - so it's hard to say exactly.

FWIW, ammonia will pass through some RODI systems I've heard, and will cause ammonia smell which is what makes up a lot of cat urine smell.

This thread might be interesting to anyone who is getting ammonia smells:
House water smells like cat urine. What is it? - Yahoo Answers

Also, more up our alley:
Chloramine and the Reef Aquarium - Reefkeeping.com

If your system isn't being monitored closely and is some or all filter elements are borderline or expired, this can allow ammonia (and other things!) into your RODI reservoir.

DI is your last line of protection and probably your most powerful tool for ammonia removal - as a bonus, monitoring its output with a TDS meter is cheap and easy.
RO depends on pressure to work, so being able to watch the pressure on the membrane's feed water at minimum is a nice bonus, but will require a minor modification to install on your system. Monitoring the pressure of the main tap water input as well gives you an even clearer picture of how your pre-filters are working.
Activated Carbon can in theory do the whole job of removing the chlorine and ammonia, but contact time would have to be significant and filter elements fresh. Ammonia is removed in a limited amount and the amount depends on local water conditions. (See second link above.)

Fwiw, I use two carbon canisters, and I'm only applying 40 psi on a 75 gpd membrane for flow. I do monitor TDS out of my membrane and DI stage, as well as pressure into the system and into the membrane. We don't have bad water, nor especially hard, but we do have chloramines...and knock on wood, I've never experienced "***** water".

(I have had laundry room issues and have stopped aerating my reservoir as a result....it was a recent practice.)

-Matt

joekool · Jan 14, 2014

If I store for more than a day I get the smell. I don't get the smell anywhere in the house.
I have about 55 psi and 4 to 6 in to the Dual DI and 0 out on my tds meter.
I get the smell even with new filters.

I need to scrub out my brute with vinegar and see if that helps.

You say two carbons. I assume you use catalytic activated carbon for chloramines and carbon for the chlorine and other stuff.

Vwtbug · Jan 14, 2014

Ya pass 2weeks I've have smelled that to.thought my cat was getting n my room.just went down pulled lid off my brut n smell the cat smell what the heck.I just got brs 5 stage also I have used it 4 times had it 5 to 6 weeks.really just when I thought I was doing good.the brut can n my room I store my top off water n that can.. Can't be leave this another problem

mcarroll · Jan 15, 2014

joekool said:
If I store for more than a day I get the smell. I don't get the smell anywhere in the house. 
I have about 55 psi and 4 to 6 in to the Dual DI and 0 out on my tds meter. 
I get the smell even with new filters. 
 
I need to scrub out my brute with vinegar and see if that helps. 
 
You say two carbons. I assume you use catalytic activated carbon for chloramines and carbon for the chlorine and other stuff.

Doing a breakdown and cleaning is always a good idea if it's been a while.   I know I'm due on my reservoir....just need the time.

55psi is going to give more flow than what I'm getting, but not sure if it nets out to 28% more.   Anyway, assuming it's close to that just for some comparisons, that means your contact time with carbon and DI stages are 28% less...even with new filter elements.  If you're using high quality filter elements you might be able to find out what flow rate your carbon was designed for and simply measure yours to see if yours is too high or just right.  (Cheapies never carry any specs.) I've tried catalytic, but never had a problem with the regular carbon block filters so switched back because they are cheaper.   If you can't run two carbon stages, I'm not sure what the best recommendation is....I don't think catalytic GAC has a lot of capacity vs a carbon block, so that could mean you have to change media a lot more frequently than you're used to if you decided to run only GAC.  The danger there is that if you run out your carbon stage without knowing it, that means you ruin your membrane with chlorine.  Being able to test for low levels of chlorine coming from the carbon stage before you run each RODI batch would be nice and probably worth while.  (Hanna makes two chlorine Checkers...I'd call and ask which is best.) FWIW, I dunno if I agree with their rationalization, but if you see their recommended filter arrangement in this link, I think I do agree with BRS that <a data-cke-saved-href="http://www.bulkreefsupply.com/catalytic-activated-carbon-for-chloramines-removal-one-cartridge-refill.html" href="http://www.bulkreefsupply.com/catalytic-activated-carbon-for-chloramines-removal-one-cartridge-refill.html">two-stage carbon is the best way to run GAC</a>.  Depends how big a deal you think it would be, but maybe consider re-plumbing the second DI stage to instead be a second carbon stage? -Matt

Edit: Wow....not sure what happened to that save, but don't have time to re-edit. I sure didn't write it like that! LOL