Basic Water Chemistry Question

Water analysis, treatment, and mineral recipes for optimum taste and equipment health.
Benny2blades

#1: Post by Benny2blades »

Tried searching google and couldn't find the answer. I have made the jump to a prosumer machine and I wanted to start off with a simple recipe for water. I made the recipe from whole latte love video on, "How to make basic brew water". The water calls for combining a simple solution of baking soda and Epson salt to 1 gallon of distilled water. :!: I used a TDS, and it is reading 210 ppm. Since the solution only contains epson salt and baking soda should I be concerned by the high ppm?

Additionally, does anyone have a good source for water quality for beginners?

DamianWarS

#2: Post by DamianWarS » replying to Benny2blades »

What was the TDS of the water you started with?

Benny2blades

#3: Post by Benny2blades »

I used distilled. 5ppm. Probably some sentiment from the glass

Jeff
Team HB

#4: Post by Jeff »

Which water recipe to make up is a lot like Coke vs Pepsi.

"rpavlis" is one of the easiest and the similar recipe with baking soda is also straightforward. From there the recipes tend to two or three ingredients. Some of those with epsom salt may produce better tasting results, with personal preferences dominating over any "science" that I know of.

Here's one of many threads on the general topic Head is spinning! Is there a very simple water recipe?

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homeburrero
Team HB

#5: Post by homeburrero »

Benny2blades wrote:The water calls for combining a simple solution of baking soda and Epson salt to 1 gallon of distilled water. :!: I used a TDS, and it is reading 210 ppm. Since the solution only contains epson salt and baking soda should I be concerned by the high ppm?
The recipe in that WLL video:


If based on distilled and mixed correctly this recipe works out to 0.83 mmol/L sodium bicarbonate and 0.70 mmol/L magnesium sulfate (or in terms of CaCO3 equivalents, an alkalinity of 41 mg/L and a hardness of 70 mg/L.) The calculated TDS (sum of the masses of each dissolved ion) would be 153 mg/L but a TDS meter measures conductivity and translates that to a rough guess of TDS. This mix would have a conductivity of about 230 µS/cm at 25 ℃, and would be expected to read in the ballpark of 115 ppm on an inexpensive NaCl calibrated TDS meter, and ballpark of 150 ppm on a '4-4-2' calibrated TDS meter at 25 ℃. So your reading does look a little high, but may be due to temperature or meter calibration being off.

Benny2blades wrote:Additionally, does anyone have a good source for water quality for beginners?
You might look into the posts and links in this forum topic: Good references on water treatment for coffee/espresso

The best single resource is probably Jim Schulman's Insanely Long Water FAQ, very complete but maybe not an easy read.
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

Benny2blades

#6: Post by Benny2blades »

I just came across rpavils recipe. I will give it a try. Based off what I found even with a tds over 200 I shouldn't have any scale because I'm not adding any calcium or lime. I hope that's the case. Scrolling through the threads and found this"One caveat to adding magnesium sulphate to your Pavlis water (which makes it into Perger water), is that if you don't use distilled or DI water, even RO might have small amounts carbonates which might combine with magnesium to make magnesium carbonate scale."

Benny2blades

#7: Post by Benny2blades »

@homeburrero thank you for that write up and links, I will definitely read them!

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homeburrero
Team HB

#8: Post by homeburrero »

Benny2blades wrote:Scrolling through the threads and found this"One caveat to adding magnesium sulphate to your Pavlis water (which makes it into Perger water), is that if you don't use distilled or DI water, even RO might have small amounts carbonates which might combine with magnesium to make magnesium carbonate scale."
Any water that you make using a bicarbonate along with a magnesium salt will have HCO3- ion and Mg++ ion, so the two can always get together chemically and cause magnesium carbonate or magnesium hydroxide 'scale'. But in practice this will not happen nearly as easily as with calcium and bicarbonate, so you can get away with relatively high magnesium hardness without seeing the limescale (CaCO3) problems that you'd get with calcium. Some of the early Perger recipes were 100 mg/L magnesium hardness and 50 mg/L alkalinity and people were reporting no scale problems.
Pat
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