Treating water hardness of 20 grains per gallon

Water analysis, treatment, and mineral recipes for optimum taste and equipment health.
Oberon
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#1: Post by Oberon »

Title gives the main gist...here are the water test results for the new cafe/bakery I'm building out (will be batch brewing coffee):

Alkalinity (total as CaCO3): 280 mg/L
Total Hardness as CaCO3: 343 mg/L (or ~20 grains/gallon)
Total Dissolved Solids: 484 mg/L
pH: 7.6

Chlorine is not a big issue; taste is not good, but not TOTALLY horrible.

For baking, hardness of around 150 mg/L is good (a fair amount of leeway here), and perfectly soft water is not). Ovens, high temp dishwasher, and brewer like things softer...thoughts?

For space and to avoid sodium, I have been considering on of the citric acid chelation systems, but read that they are not strongly recommended for hardness of 10 grains/gallon...

For the time being, plumbing is a fairly blank slate, so I have some flexibility on that front.

Advice???

Thanks much...

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homeburrero
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#2: Post by homeburrero »

Your numbers indicate that you could use either a decarbonizing filter (aka WAC resin filter, aka hydrogen ion exchange filter), or a simple conventional softener to reduce potential scale problems in your batch brewer. Looking at Fetco as one example, they appear to recommend softening when the water is over 5.5 grains of hardness, and for hard water sell a BWT bestmax, which is a two stage charcoal plus decarbonizing filter, for that purpose. Otherwise they sell a high volume charcoal filter. You generally want charcoal filtration in the system to get rid of chlorine/chloramine and off-tastes and odors.

For softening, a conventional rechargeable salt based softener would be far cheaper, and you could use potassium salt rather than sodium salt. Your brew water would be expected to end up with higher bicarbonate alkalinity than you would get from no softening or from a decarbonizing filter, and that might impact the taste. (Note that if you do no softening at all, you will expect some reduction of both hardness and alkalinity of the heated brew water due to calcium carbonate scale depositing in the machine.)

I know very little about batch brewers, but I know that they don't heat water much above around 200F and would not have the scaling issues of an espresso machine. Best bet is to consult the manufacturer or supplier of your batch brew equipment for specific advice. Unless they advise a TAC or other saltless conditioner, I'd steer clear of that. The so-called 'citric acid chelation' system looks especially dubious to me.
Pat
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Oberon (original poster)
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#3: Post by Oberon (original poster) »

Thanks for that...and I agree I want some carbon filtration for taste/oder especially, and I need some scale reduction for my equipment (which includes ovens with steam generators and a high temp dishwasher and electric water heater...the method for that later is where I'm hung up...

Salt based ion exchange systems are well established known quantities and they work...but leave you with sodium (and more sodium with harder water, since they exchange sodium for the hard minerals). They also require refilling, generate waste water, and put plenty of sodium into the waste stream. Potassium is much more expensive and less effective (or requires more salts).

SO... if I did go with a salt softener, I would be tempted to combine it with an RO system with a remineralization cartridge for my coffee/drinking water/ice. But I have questions about what the best type of remineralization treatment would be, as many are focused on supposed health of putting calcium back in and making the water more alkaline than for making good coffee.

I am also a bit interested by some of the salt free conditioners, like the TAC systems (not sure why you would steer away from them???), citric acid, and others. Just looking at a TAC system like Pelican, I'm not sure how sending my water through that system would end up in terms of coffee/drinking.

I'm contacting Prima and Global Customized Water to see what guidance they can give...

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homeburrero
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#4: Post by homeburrero »

Oberon wrote:I'm contacting Prima and Global Customized Water to see what guidance they can give...
Good idea. Let us know what you learn.

Oberon wrote:I am also a bit interested by some of the salt free conditioners, like the TAC systems (not sure why you would steer away from them???), citric acid, and others.
They are new and some of them are unproven (many would call them snake oil) But the TAC softener is proven technology for scale prevention in water heaters, and so I think it should be fine for a batch brewer. Here's a discussion thread that might be of interest: Template Assisted Crystallization (TAC) Water conditioning .

The citric acid one is very unspecific about any chelation or sequestering agents that may or may not be in their proprietary media. Citric acid will of course reduce scale, but it does so by acidifying the water and reducing the carbonate alkalinity, which may sometimes be a bad idea.
Oberon wrote:Just looking at a TAC system like Pelican, I'm not sure how sending my water through that system would end up in terms of coffee/drinking.
Agreed. I don't think we have a good handle on the effect of plain hardness ions on coffee extraction, matter less the effect of chelated/sequestered ions.
Oberon wrote:But I have questions about what the best type of remineralization treatment would be, as many are focused on supposed health of putting calcium back in and making the water more alkaline than for making good coffee.
I agree. It may be best to stick to old fashioned calcite remineralization filters, or perhaps a calcite + corosex filter made for coffee equipment. You don't get much mineral but at least they are conservative and somewhat predictable.
Pat
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Ciaran
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#5: Post by Ciaran »

If you don't have any corrosion vectors in your water, i.e. chloride, sulfates, super high fluoride, low pH etc, you should just blend some of the filter source water back into your product water and save on the remineralization.

Your calculated TDS is actually closer to 623 ppm, someone must have using a salinity meter to get the 484 number.

TAC has limits on hardness. And Iron will interfere, so you need to know the iron in your water before using it. I have no direct experience with installing these, but friends who have, have told me the upper limit is around 10 gpg. And you are not removing any hardness. It's still going to build up in the boilers of espresso machines and clog steam ovens. It supposedly will just be easier to remove.

Iron is also an interference for a couple of other salt-free "technologies". So be sure to investigate that. It's also a challenge to remove.