Reading Chlorine residual on water report

[catalanotte]

I have recently made a switch to chlorinated surface water for brewing, using tap water with the following report available. Milwaukee Water Report I have tasted many beers with chlorophenols and am very worried about this water switch. I am good with the general alkalinity and mineral issues, and plan to use this water with a little bit of gypsum and calcium chloride, along with a small acid addition for amber/IPA beers. My question has to do with treating the chloramine with campden (SMS) tablets which is new to me. Most of what I have read says 1 tablet for 20 gal of source water, but I am a geek and want to see the math. I am also referencing Chapter 8 in the book Water (Palmer/Kaminski) which has a formula approach. Using this Table 21 in the book the correct amount of SMS is 2.674 mg/l for each 1.0 mg/l of monochloramine. The linked water report indicates 1.54 mg/l of chlorine reported as total chloramine residual. So at 1.54 mg/l and 20 gal of water ~ 1.54mg/l * 2.674 * 20gal * 3.8 l/gal= 313 mg of SMS or if I err on the side of caution at 1.8 mg/l (high end of range) this is 365 mg SMS. Since a tablet is 440 mg, this seems close enough to use a full tablet and matches the general suggestion. Do these numbers make sense and is rounding up to to full tablet appropriate? Are there any issues with using too much SMS other than the very small additions of sodium, sulfate, and chloride ions? The added befit appears to be a very slight reduction in alkalinity.

I don't need RO for this water source, except for vary pale beers, but does RO remove all chloramines? If so, which do most people use, RO or campden?

 

[IslandLizard]

Instead of using the hard tablets, I'd use an equal amount of Sodium (or Potassium) Metabisulfite powder. Your LHBS should have it. Keep dry in a tight closing jar.

A quarter teaspoon of the Meta powder treats 20 gallons, so a 1/16 of a teaspoon threats 5 gallons. You could use a bit more, even double if in doubt, it leaves no flavor.

The (fine) powder dissolves immediately and doesn't need to be crushed before adding, which the tablets would require. Just give it a good stir.

I add the Meta powder while filling up the bucket, using a long vinyl hose to reduce the amount of air (oxygen) being incorporated. Then give it a good stir when the bucket is full.

Notes:
Our tap water is very soft, so good for pretty much all brewing. Now we have just Chlorine, no Chloramines, but the meta powder ought to work equally well.

 

[day_trippr]

An RO membrane does not remove chloramines. In fact I believe they can be damaged by chloramines especially if the pH is high enough. But because RO systems typically come with pre-filters that include activated carbon (or even catalytic carbon), and the RO system throughput is typically quite low, that provides enough contact time between the water and the carbon "filter(s)" to take out the chloramine...

Cheers!

 

[Bramling Cross]

Do these numbers make sense and is rounding up to to full tablet appropriate? Are there any issues with using too much SMS other than the very small additions of sodium, sulfate, and chloride ions? The added befit appears to be a very slight reduction in alkalinity.

I don't need RO for this water source, except for vary pale beers, but does RO remove all chloramines? If so, which do most people use, RO or campden?

I'm lazy so I've been using a full campden tablet to treat my ~10gal water bill for pretty much as long as I've been brewing. During that time I've found it necessary to carefully solve a lot of problems with my beers, but I've never found any compelling reason to reexamine my campden use.

In addition to being lazy, I'm also cheap. Buy campden tablets by the pound, rather than those little rip off bottles.

 

[IslandLizard]

In addition to being lazy, I'm also cheap. Buy campden tablets by the pound, rather than those little rip off bottles.

Absolutely!
"Laziness" should entice anyone to buy "Meta" powder (also sold by the pound) instead of the tablets. No crushing, no binder, no waiting for it to dissolve.

Even using 2x or 4x the recommended amount of Campden/Meta won't be an overdose either. You'll end up with a tad more Sodium (or Potassium) and Sulfate ions. None would harm your beer or even be enough to taste.

 

[Bramling Cross]

"Laziness" should entice anyone to buy "Meta" powder (also sold by the pound) instead of the tablets.

A couple years ago, while carefully measuring out a batch of trifecta into a ball jar the penny finally dropped, "Hold on! Is this just a bag of campden tablet powder?!"

After an internet search, I found myself sitting, chin in hand, looking at all the neat little bags of vacuum packed campden tablets from the 5lb bag I had bought ten years ago. Hmmm.

 

[IslandLizard]

"Hold on! Is this just a bag of campden tablet powder?!"

Basically, yes, but without the binder component, which makes the tablets so difficult to dissolve without first pulverizing them.

I had a whole bunch of those tablets too, then I read about the added binder. In the mortar they went... When they finally ran out (took almost forever), I got that pound of K-Meta.

 

[Buckeye_Hydro]

An RO membrane does not remove chloramines. In fact I believe they can be damaged by chloramines especially if the pH is high enough. But because RO systems typically come with pre-filters that include activated carbon (or even catalytic carbon), and the RO system throughput is typically quite low, that provides enough contact time between the water and the carbon "filter(s)" to take out the chloramine...

Cheers!

RO membrane chloramine tolerance is very high, but where there are chloramines, you almost always have some free chlorine. RO membrane tolerance for free chlorine is much lower (~200 to 1000 hrs @ 1 ppm).