Many brewers rely on softened water, often provided by household water softeners, to adjust the water hardness. While these systems are designed to reduce hardness, they can add sodium to the water, which may affect your beer’s taste and quality. Understanding how water hardness impacts brewing and how to manage it is crucial for achieving the perfect brew.
What is the role of Water Hardness in brewing?
Water Hardness is the amount of dissolved Calcium and Magnesium in your water. Both of these minerals are important in the brewing process and have different effects. Calcium affects the finish of your beer; helps control the Mash pH and helps clarify your beer. Magnesium also controls the Mash pH and is an essential nutrient for yeast growth.
The most important aspect of Total Hardness will be its effect on reducing your Mash pH. When looking at Residual Alkalinity (A brewing specific term, so not one you’ll learn in Chemistry Class), you can reduce it by either reducing Alkalinity or increasing Water Hardness. When brewing lighter beers, you’ll want to aim for a lower Residual Alkalinity.
Water Hardness Levels in your brewing water
Water Hardness can be measured as Temporary Hardness, Permanent Hardness, or Total Hardness. For brewing purposes, temporary hardness is easier to remove than permanent hardness. Total Hardness is just the combination of the two.
For Total Hardness, the minimum recommended levels are around 150 ppm. While this level isn’t necessarily crucial on its own, it helps balance alkalinity, which in turn reduces mash pH and ensures enough calcium is available for brewing.
How to Measure your Total Hardness levels
There are two ways to measure Total Hardness, the Craft Pro Test Strips and the Craft Pro In-Lab Test Kit.
DIY Test Strips
The Craft Pro DIY Test Strips will give you an easy, affordable way to measure Total Hardness with each batch. Because many factors can affect Total Hardness, it should be spot checked every time you brew beer.
The test strips will give you results in a range, meaning you will know if your Total Hardness is 0-50 ppm, 50- 120 ppm, etc.
Craft Pro In-Lab
The Craft Pro Master Brewers Test Kit will allow you to send a water sample to our EPA-Certified lab and get exact concentrations for your brewing water or any brewing liquid.
You will know exactly what your Total Hardness is, as well as exact concentrations for other parameters and several brewing specific calculations such as Residual Alkalinity.
How to adjust your water’s Total Hardness level for brewing
Increasing your waters Total Hardness can be done with brewing salts. “Gypsum (calcium sulfate), Calcium Chloride, Epsom Salt (magnesium sulfate), Magnesium Chloride, Chalk (calcium carbonate), or Pickling Lime (calcium hydroxide) additions can be used to increase the hardness.” (Brun Water)
These salts can be used based on what levels of other minerals you want to optimize for such as Magnesium, Calcium, Sulfate, etc.
How to soften your water
While higher Total Hardness is typically a positive for brewing, there are cases where you’d want to decrease this level. Some darker beers will want slightly higher Alkalinity, so if your water profile calls for it you may want to reduce your water’s hardness.
The other case is for cleaning your equipment. Like in most residential homes, there are negatives to having hard water. It can cause cloudy water, interfere with some cleaning agents, and cause scale to build up on your equipment. This scale not only makes your equipment look aged but can interfere with its use and decrease how long it will last. Costing you money for equipment replacement.
Diluting your water to reduce hardness
If your Hardness levels are high another option is to Dilute your water with RO or distilled water. This will just be a matter of doing the math to figure out the adjustments. If you want to aim for 150 ppm and you are currently at 300 ppm, you will need to use a 1:1 ratio if your RO water is at 0ppm.
Reducing Hardness by boiling
If your water is high in Temporary Hardness, boiling it for at least 15 minutes and then filtering out the precipitate can remove the calcium from the water, reducing Hardness. This process will only remove the calcium and not the magnesium. Plus, it will only remove temporary hardness, not permanent hardness.
This means that for a homebrewer who wants to try this method and then re-test their water, it can be worth testing out as an easy and cheap solution. But it’s not suitable for professional brewing where you need consistent results.
Home Water Softener
Approximately 25% of homes have a water softener system, but is this suitable for brewing?
Most household water softeners are Ion-Exchange Softeners. If you don’t know if your system is an Ion-Exchange, the easiest way to tell is if you must add salt to your system. If your system uses salt, it’s an Ion-Exchange.
Because every water softener will replace a different amount hardness with sodium, and all water is at a slightly different level of starting hardness, some softened water is suitable to brew with and some isn’t.
Besides testing your water after treatment, there are a few factors to look for. The first is the sodium level of your treated water. If it has a salty taste after treatment, that will carry over to the beer. While this may not affect fermentation, it could leave you with a salty beer.
The second is the starting hardness. Because Ion-Exchanges replace minerals with salt, if you start with overly hard water, you will end up with elevated levels of sodium. If you only had slightly hard water and your water softener doesn’t aggressively replace the minerals, it may still be suitable.
Conclusion:
In brewing, water hardness plays a critical role in achieving the desired beer quality. Both calcium and magnesium, the two main minerals that contribute to water hardness, serve essential purposes such as controlling mash pH and supporting yeast growth. While hardness benefits the brewing process by lowering mash pH and providing necessary minerals, there are instances, such as brewing darker beers or maintaining equipment, where reducing hardness may be preferable. Homebrewers can adjust water hardness through brewing salts or softening techniques like dilution or boiling, but consistent results require regular water testing to fine-tune the levels for each batch.
