Water Hardness Question

I'm doing my 1st AG batch this weekend. I have an under the sink RO system, and up till now I've been using that water to brew with. We have a water softner as well, but I just discovered that my kitchen sink cold water is not softened.

The only thing I know about the local water is that the hardness is 11 grains. I'll get it tested, but for brewing this weekend would you recommend I just use the tap water or use the RO water and add some minerals? I'm making a Pale Ale, if that matters at all.

To predict and control, I'd go with the RO and adjust with minerals....
How big a batch? If your RO system is like mine, I can't get more than a gallon and a half out of it at one time....takes several hours to get more.

My water calculator (Brunwater) tells me to add .5 g/gal of Gypsum and Calcium Chloride and .2g/gal of Epsom Salt to RO water to obtain a Pale Ale profile

I also discovered that softened water is not good for homebrew.....

I'm doing 5 gallons. I can only get a couple gallons from my system at a time as well, but it refills quickly, so if I can manage 6 or 7 gallons over the course of a few hours I think.

I assume you would add all of those minerals into the mash? Or would you only put half in the mash and the rest in the sparge water?

I'd use the RO. Half to 1 tsp of calcium chloride and half to 1 tsp of gypsum (I'd start at at a half of each) will be just fine for an IPA. You don't really need Epsom salts but if you want to put some in anyway a little won't hurt.

To increase the production rate of your RO system leave the valve open (with a hose running to some collection vessel). This prevents the pressure from building up in the bladder tank. That pressure reduces the volume of water produced per hour.

Thanks. So if I do 1/2 tsp of each, would that be all in the mash or 1/4 tsp of each in mash and 1/4 tsp in sparge water?

That would be (1/2 tsp each) per 5 gallons of RO water however you want to divide it up. Much easier (IMO) to treat the whole volume at the outset.

The problem is, the pot I'm going to use to heat water is only 5 gallons, so I have to fill and heat it twice.

ajdelange said:

. . . You don't really need Epsom salts but if you want to put some in anyway a little won't hurt. . .

Click to expand...

Magnesium is good for yeast flocculation....and with RO water, you don't have any. Another local homebrewer has been extensively experimenting with straight RO water and mineral additions and has reached the conclusion that epsom salts are dang near necessary when doing all RO.

and don't take my word for it...take Palmer's
http://www.howtobrew.com/section1/chapter6-9-1.html

That says that since I brew with 0 magnesium (effectively - the water is softened before going through the RO system) I should have trouble with flocculation. But I don't. So much for that theory.

I didn't take your word for it. Here's what John says:

"Usually the wort supplies all the necessary mineral requirements of the yeast, except for zinc which is often deficient or in a non-assimilable form."

That's true. There is plenty of magnesium in malt. In fact the amount of magnesium that gets added from a few mg/L Epsom salts addition to the water (remember that they contain 7 waters of hydration) is small relative to the amount contributed by the malt.

Magnesium is not required for flocculation. It may help but you really should must have some calcium and that takes care of the flocculation. What magnesium is needed for is as a co-factor for some of the enzymes involved in fermentation. Malt supplies plenty for this.

It is also true that worts may benefit from addition of a bit of zinc and most yeast nutrients contain so.

Bottom line:
You don't need to add magnesium salts.
It won't hurt to add some magnesium sulfate if you really want to or if you want the particular bitter/sour flavor that magnesium imparts.
I might help to add some zinc.

No...it doesn't say you should have trouble. It says you could avoid trouble or if you have trouble, magnesium could be helpful. It also says, yes the magnesium may be sufficient but it can be inhibited.

Maybe your flocculation would improve with a magnesium addition.

And just prior to what you quoted is what I'm referencing....

But it's homebrew...to each his own. Add or don't add what you want but if it won't hurt and might help, why not?

Malt is a volcano. Epsom is a cow fart. Beneficial or not, it's pretty insignificant.

I brew wonderfully flocculated crystal clear beer with 0 added Mg. Tally me up.

PS -- AJ is not a Palmer Reader. He's a source.

GotPushrods said:

Malt is a volcano. Epsom is a cow fart. Beneficial or not, it's pretty insignificant.

I brew wonderfully flocculated crystal clear beer with 0 added Mg. Tally me up.

PS -- AJ is not a Palmer Reader. He's a source.

Click to expand...

Well, I never thought of it as volcano vs "cow fart" so that made me laugh.

I never add magnesium to my RO water. Some do, but I don't like the strongly bitter/sour flavor I pick up in it that AJ deLange described. A little won't hurt or be perceptible, but there is also no benefit. As AJ mentioned (and so did Palmer), malt has plenty of magnesium on its own.

And as far as the last line about AJ being a source for Palmer, I forgot to mention to AJ that I spoke to Palmer about the new book, and does give a ton of credit to you. He said it should be out in Octoberish? He said he was checking over the technical descriptions under the photos (forgot what he called that).

I asked the question, why not? It's been answered....evidently the fart can be tasted by some.

I don't add it either...but I don't brew exclusively with RO water.

Yooper said:

He said he was checking over the technical descriptions under the photos (forgot what he called that).

Click to expand...

I'll tell you what I call it, one big PITA! But it's got to be done. Here if you make a mistake you can go back and edit the post. With a book you can't. No author wants to be responsible for publishing an error and I'm sure John and Colin (and the copy editors) have gone over it with a fine tooth comb. Not to mention that Martin and I scoured it for technical solidity. But we all know that some goofs are going to slip through. We've certainly all seen them in other technical (and non technical) books.


WRT to the subject at hand: In the final analysis the decision to use epsom salts and how much should be arrived at in the same way as the decisions that set the quantities of NaCl, CaCl2 and CaSO4 and that is by experimenting with it. If you brew a beer with none and have, or fancy you have, flocculation problems and then brew a beer with some and they are ameliorated, or you fancy they are, then make a tentative decision to use it. Then comparatively taste the beers. I'd live with slightly slower flocculation (I'm a lager brewer primarily) for the sake of better tasting beer. For the record, I can't say I noticed any detriment in flocculation or any other when I started brewing with magnesium free water. But neithermore have I tried dosing any magnesium into my RO beers to see if they are improved. Based on what I know and my experience has shown there wouldn't be much point but only a series of batches exploring this variable would tell for sure.