chloramines and carbon block

GHill762 · Dec 11, 2014

OK chemistry folks.. RHF, I've read some comments from you as well as your article on this, interested in seeing your current thoughts on it..

I recently replaced all my filters, membrane, and resin. I'm in the process of moving and figured I'd get all new stuff since moving to a different water supply (well water to a municipal water supply) and they needed replaced anyway. I got a 1 micron sediment block and the 5 micron and .6 micron carbon blocks from BRS (labelled Matrikx) as filters before the membrane. I flushed them all individually in the setup process and water is coming out at 0 tds per my meter.

Here are the blocks: 10" MATRIKX Carbon Block - Bulk Reef Supply

As far as city water quality, last I tested (about a year ago, could be different now I guess) it was around 50-60 TDS range, so not too bad (MUCH better than the ~550 I average on a well). The city water quality report shows an upper limit of 3.5ppm chloramines tested at tap. They initially treat water with chlorine to disinfect it, then later in the process add ammonium sulfate to create chloramine(s), I assume that is SOP.

I didn't know there was chloramine in the city water or I'd have ordered the correct carbon blocks at the time.

I sent an email to KX Technologies (company that makes the Matrikx carbon blocks BRS sells) with my concerns and this is the reponse I got:

"Hello,
In response to your website submission, unfortunately, neither of those blocks reduce chloramines. The attached document gives some quick facts about chloramines and we do carry a chloramine reduction filter. I will be happy to send you one if you give me your address...."

She also attached a word doc with a bunch of educational stuff on chloramine.

So, do I have reason to be concerned? I've not run much water yet, but I don't want to fry my RO membrane and I certainly don't want to poison my tank. It seems I am getting conflicting information depending on where I look. what is the current thought on this? please help?!?!?

Any help or suggestions are appreciated.

Thanks,
Garrett

Randy Holmes-Farley · Dec 11, 2014

Almost everyone that I surveyed that has chloramine in the water and an ordinary carbon block (including my system) had no chloramine in the effluent.

My suggestion is to buy ordinary (cheaper) blocks, and if you are concerned, test the effiuent with a cheap chlorine kit (it need not be a chloramine kit).

If none is there, you are good to go. If some is there, then you may need a better block.

GHill762 · Dec 11, 2014

Thanks Randy, that's basically what I was expecting you would say. I'm glad you responded. So does it have any effect on the lifespan of the ro membrane or overall tds?

Are you saying it's really not worth it (unless there is detectable chlorine) to run the chloramine specific carbon blocks?

Randy Holmes-Farley · Dec 11, 2014

Yes, if chlorine or chloramine is getting to the RO membrane, it can damage it, so you would not want that going on for long.

I have never bothered to use a special carbon block, and I've only replaced one membrane in 19 years. Of course, YMMV.

GHill762 · Dec 11, 2014

Gotcha. That's a really long time..

Thanks Randy!

Randy Holmes-Farley · Dec 11, 2014

You're welcome. If you detect anything getting through, let us know!

GHill762 · Dec 12, 2014

Well, since they offered a free chloramine specific carbon block I'm going to take them up on it. I didn't contact them with the intent of getting anything for free, only information, but we shall see how this new block performs (apparently it's a brand new carbon block specifically for chloramines that won't actually be released for sale until 2015, but they had some samples sitting around).

I'm nearly certain I'd be fine with the standard block, but I figure this will give me peace of mind.

Thanks for the help Randy.