Home Brewing Water Chemistry Basics

by Karl | Last Updated: May 31, 2021

Water. It makes up 95% of beer and some say it’s the most important factor to good beer, but what is pH and how do I adjust my water? And does any of it really matter?

If you’re looking for a simplified look into brewing water, then you come to the right place.

I’m Trent Musho, and this is the Bru Sho. Let’s talk H2O.

When starting out brewing, it makes sense to master an understanding of each of the main ingredients. Hops and yeast are the simplest to get an understanding of, since they’re accessible to any level brewer. All you need to do is try them out.

And moving to all grain is probably one of the biggest leaps you can make to improve the quality and control of your beer. But for some reason, water is hard for a lot of brewers to get their heads around. Maybe it’s all the elements and names. I know I struggled at chemistry in high school, or maybe it’s just overlooked.

Since we often hear the phrase. If you liked the way your water tastes, that will make good beer. Even I’ve said that from time to time and for the beginner brewer, I still stand by that. But if you’re looking to take your beer from good to amazing, understanding a little bit of water chemistry can really be key.

But don’t worry you don’t have to be a mad scientist to understand this stuff. I’m going to keep things super simple so you can get to the basic understanding to start taking those steps towards better beer today.

Before I jump into water and water adjustments, please take a second to like this video and consider subscribing for more brewing one-on-one videos like this.

All right, let’s get into it. Let’s start by talking about some of the types of waters you use for brewing.

Tap water, filtered, or reverse osmosis water and distilled water. Tap; This is when the general rule of thumb comes into play. Good tasting water makes good tasting beer. Obviously, if your tap water tastes awful, don’t use it. But if you like it, then you can use it. It’s super helpful to get a water report from your local city, or you can send a sample of your water to a company like ward labs.

It will then send back a report that tells you what minerals and elements are present in your water. The reason this is important is that these minerals have a major impact on your beer. Whether that’s mouthfeel, apparent bitterness or general taste. I’ll go over the specific things to look out for in a little bit.

Once you have a water profile, you can then determine the adjustments you need to make with water salts. A potential negative aspect of tap water is that you get what you get. You can’t really take away certain elements of water.

Also one major thing to be conscious of is if you’re using tap water with chlorine or chloramines, which are usually found in city water, it can really ruin your beer. It’ll give your beer a very medicinal, almost plastic-y or bandaid flavor.

Luckily, the easiest way to remove these is you use a Camden tablet, just add one tablet. It’s good for about 20 gallons of water.

I usually add in the water the night before, but I’ve heard it begins working almost immediately. Do not skip this step if you use tap water. Last thing I’ll say is that if you’re collecting city water, the mineral levels can fluctuate, which you make it hard to replicate the same profile every time. It’s just something that you consider.

Filtered or R.O Water. The biggest benefit to filtered water is that you don’t have to worry about all that serious stuff that your city might put into your water. A filtration system does a great job of stripping out almost all the contaminants in the water, but additionally, it will remove a lot of the minerals as well.

This means you’ll need to add back in more water salts to make for the losses. It’s probably still in your best interest to get your water tested after filtration, to have a better understanding of where you’re starting.

It does come at a bit of a cost. I can take a bit longer to collect your full volume. You can also use one of those giant water jug fill ups, but again, I recommend getting it tested and sticking with the same one. So you can have some consistency.

Distilled. This is the cleanest slate possible. Basically all levels of minerals are zero. So you really need to bring the adjustments to get the water to the right levels. If you really like consistency, this is the method for you.

Now let’s take a look at a water report. There are six key minerals of importance for beer. Calcium is important to yeast, enzyme, and protein reactions, both in the mash and in the boil.

  • Magnesium is an important yeast nutrient.
  • Sodium can run off the beer flavors and accentuate the overall flavor of the malt.
  • Sulfate accentuates hop bitterness, making the beer seem drier and more crisp.
  • Chloride accentuates the flavor and mouthfeel of the beer.
  • And bicarbonate helps buffer pH or the acidity of the beer.

You don’t really need to know all of these to make a good beer, but when you get your water report, you’ll need these numbers to input into a brewing software. They’re the ones that have the biggest impact on your beer. And they’re also the ones you can easily adjust.

Probably the two biggest names mentioned are sulfate and chloride. As these are the two levers you can pull to affect the bitterness and mouthfeel of your beer. They’re often represented as the ratio of sulfate : chloride. The more sulfate there is, the more bitter your beer will seem and more chloride can mean a more full body.

For example, usually a West coast IPA will lean more sulfate and a hazy new England IPA will lean more chloride.

I do recommend using a brewing software when adjusting water.

It doesn’t matter which one, there are even some great free ones online I’ll link to a few in the description. The benefit of using a software is that you can pick a style of beer you’re trying to make and it will estimate the minerals needed for that particular style.

Then you add in the current water profile and it will tell you which water salts to add, to get close to the amounts needed for that style.

Speaking of water salts, let’s talk for a moment about some of the most common ones you’ll use to adjust your water. All of these are sold at home brewing stores and some you can even find at your local grocery store. l’ll link to all the products I discuss in the description box as well.

There are three main ones we use more often than others.

  • Epsom salt, also known as magnesium sulfate, as the chemical names suggests increases magnesium and sulfate levels.
  • Gypsum also known as calcium sulfate. Same here. This one increases calcium and sulfate levels.
  • And calcium chloride, which increases calcium and chloride levels.

Other water salts are table salt, also as sodium chloride and baking soda or sodium bicarbonate, which lowers the acidity of the mash and has a bit of sodium as well.

Using your brewing software. You’ll get the amounts of each of the above that you need. It usually is minuscule amounts unless you’re starting from distilled or RO water, which means you will probably buy these salts one time in the last year for dozens and dozens of batches.

Also just to know an accurate scale is definitely needed for this. I usually toss all my water salts in just before I mash, as the water’s heeting up almost to strike temp. That way the warm water will help dissolve the additions and there’ll be ready for mash time.

The last water adjustment I want to cover is for adjusting the pH of your mash or wort. PH is a scale of acidity from zero to 14, with zero being super acidic, like battery acid, acidic and 14 being super basic, like drain cleaner basic.

And right in the middle is seven, which is neutral. This is where pure water is.

A finished beer has a pH of somewhere between four and five and then mash should have a pH of 5.2 to 5.6. And that’s really the target that we’re worried about when it comes to brewing. The reason is because during the mash, if the pH is not in that range, you’re not get as much efficiency converting the starches and the grains to sugar.

Grains in general are a bit acidic. The darker the greens are usually the more acidic they are. There are even some acid malts that are specifically made for lowering the pH.

But when we add grains to water, which is at around a pH of seven, it will lower it slightly, but often not enough to get to that 5.2 to 5.6 range. That’s where an adjustment needs to be made by the brewer.

In order to determine where your pH is at you’ll need a pH meter. Don’t bother with the strips and don’t bother with the cheap pH meters online. I’ve gone through too many of those to count. And every time I ended up throwing one of them out after a few months.

If you’re serious about pH adjustment, then invest in a quality pH meter. This one’s been doing me wonders and it’s not too expensive…

The way it works is pretty simple. You pull a sample of wort put your pH meter in it, and it gives you a number. If your pH is too high, you’ll need to add some acidity into the mash to lower it.

Easiest way is to use an organic acid like lactic acid or fosforic acid. Like with the water salts, you’ll buy this and only use a little at a time. So it’ll last you a long while.

And your brewing software can also make predictions of how much to use to get the proper pH. The best way to go about it is to add a little into your mash, mix it up, give it a minute or two, and then take another measurement to see where you’re at. Once you’re in the right range, go ahead and stop and let your mash ride.

If you overshoot your pH, you’ll need to raise it back up by using something like baking soda. Besides using these acids, you can also use gypsum or calcium chloride to lower your pH in a pinch.

So those are the ways you can adjust water, but does any of this really matter?

In short, it only matters if you want it to matter. If you’re making beer you love and you don’t want to get more complicated, then that’s fine. Keep doing you. But if you want to have a little more control, then this is one area we can really tweak your beers to your liking.

I almost always just my water profile these days. It’s easy enough just to toss in a bit of water salts before brewing, as some extra assurance that my beer will just be a little bit better. And even if I don’t feel like weighing out individual salts, I know I can always play with that sulfate to chloride level to make my beer apear more bitter or more full. So I’ll just toss in a little more of one or the other.

I don’t always adjust my pH though. Maybe that’s just me. But most of the time, my beer finds a way and the mash and the wort will buffer the pH levels into the right zone all by themselves.

You can do all these adjustments or you can do none and you’ll still make good beer, but I hope maybe you learn something and that this demistified the Waterworld a little bit.

There’s so much more information out there and details on the subject. And if you want to learn more, I suggest checking out for the resources like the Bruin water spreadsheet or the water book by John Palmer and Colin Kaminski.

Also try giving water adjustments a chance. And if you do let me know, I know your beer will thank you for it. Also consider joining the discord server to connect with other home brewers and discuss various topics related to our favorite hobby.

The invite link is in the description, happy brewing and cheers.

Lead marketer, brewer, dad, and husband. Pretty much an all-round awesome guy.