Alkalinity, Testing Your Tap Water

(That's water to the rest of us!) Beer is about 95% water, so if you want to discuss water treatment, filtering etc this is the place to do it!
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Chappie519

Re: Alkalinity, Testing Your Tap Water

Post by Chappie519 » Tue Mar 03, 2009 8:12 pm

Cheers Chris! Would I get that at a fish shop?

Chappie519

Re: Alkalinity, Testing Your Tap Water

Post by Chappie519 » Tue Mar 03, 2009 8:49 pm

Cheers Chris!

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Hogarth
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Re: Alkalinity, Testing Your Tap Water

Post by Hogarth » Tue Mar 03, 2009 10:13 pm

Received my Salifert KH/Alkalinity Test Kit today so naturally I've spent the evening playing with it. Funnily enough my results have been the same as ADM's -- an alkalinity figure that is rather higher than I'd previously believed and suspiciously close to the water report's 'Total Hardness' figure. On the other hand my mash PH is usually too high despite adding CRS, so perhaps the kit is telling the truth and I need to put more in. More experiments to come. :D ... It's amazing how much you learn about tropical fish while researching alkalinity.

adm

Re: Alkalinity, Testing Your Tap Water

Post by adm » Tue Mar 03, 2009 10:23 pm

Chris-x1 wrote:ADM has my kit and the Salifert kit, perhaps he can confirm whether the two values are similar.
I will do.

Funnily enough, I bought a bottle of de-ionised water today for exactly that purpose.

In fact, I might even go and do it now. It means a trip past the beer taps though.

adm

Re: Alkalinity, Testing Your Tap Water

Post by adm » Tue Mar 03, 2009 11:10 pm

Right - the results are in....

Chris's kit: 135mg/l CaC03
Salifert Kit: 137mg/l CaC03

Both test water samples from the same glass.

Personally, I'd say they are identical within my expected range of pilot error!

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Hogarth
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Re: Alkalinity, Testing Your Tap Water

Post by Hogarth » Wed Mar 04, 2009 12:03 am

Very impressive. Then if these kits are accurate I've got a whopping 263mg/l alkalinity to deal with. Next time I brew I'll dose it with CRS accordingly and test it again to see if it tallies.

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Hogarth
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Re: Alkalinity, Testing Your Tap Water

Post by Hogarth » Wed Mar 04, 2009 12:38 am

I think it's CaCO3 -- I got it by multiplying my meq/l by 50.

Other Londoners report an alkalinity figure of around 215, which is why I was surprised by mine.

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Hogarth
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Re: Alkalinity, Testing Your Tap Water

Post by Hogarth » Wed Mar 04, 2009 2:13 am

Thanks for that, Wallybrew and Chris.

It's true I got a mash of PH4.2, presumably after an overdose of CRS. On the other hand, since assuming an alkalinity of 210 and treating accordingly, all my mashes have been too high -- 5.5, 5.6, and 5.8 respectively. That's why I bought the Salifert kit, which three times has given me 15dKH / 5.37 meq/L / 268.5 mg/l of CaCO3 with minor variations.

The point is, I'm not taking any position on this because I'm the world's lousiest scientist, and the fact that everyone else -- including a fellow Brixtonian using one of Chris's kits -- gets 200-220 certainly makes me suspicious of my own readings. All I know is, something's not right.

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Re: Alkalinity, Testing Your Tap Water

Post by WallyBrew » Wed Mar 04, 2009 2:08 pm

Hi Hogarth

Total alkalinity from a boosted system in Clapham Park Road (a stones throw from Brixton). Taken on 16.2.09. checked today = 206mg/l as CaCO3.

Total alkalinity from a cold down service in Threadneedle St. taken on 9.2.09. checked today = 216 as CaCO3. And way back in the last century (1995) the alkalinity of the water taken from a drinking tap in the place where some 650 ego maniacs waste most of our money the alkalinity was 209mg/l as CaCO3

I also have a result from near Electric Avenue of 198, however, I'm not convinced that the sample bottle it was in was satisfactory.

Do you have any colour defects in your vision? colour blindness test , as I believe that the indicator used may not be colour defect vision friendly.

In the kit I have there is a bottle marked 6.5 KH +/- 0.3. If you have one have you tested it?

Chappie519

Re: Alkalinity, Testing Your Tap Water

Post by Chappie519 » Wed Mar 04, 2009 4:50 pm

Hi,

Happened to be passing the fish shop today and picked up This

I just checked my water and the kit gave me a reading of carbonate hardness about 36ppm KH ,and 2 "degrees"dKH.

My question is, Is this any use to me this figure?

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Re: Alkalinity, Testing Your Tap Water

Post by WallyBrew » Wed Mar 04, 2009 5:06 pm

The dKH should be hardness in german degrees. For some stupid reason the germans measure hardness as CaO in parts per 100,000
Each dKH units is equal to 17.9mg/l of CaCO3

So yes is the answer. Your alkalinity is 36mg/l

Chappie519

Re: Alkalinity, Testing Your Tap Water

Post by Chappie519 » Wed Mar 04, 2009 5:17 pm

Cheers Wally!

So using grahams liquor treatment calc here I would put 36 into the hardness box or the alkalinity box at the top? and that would be in CaCO3?

Cheers

garwatts

Re: Alkalinity, Testing Your Tap Water

Post by garwatts » Wed Mar 04, 2009 6:47 pm

Does anyone have the low down on the water in the Swindon area at all please? :?

Graham

Re: Alkalinity, Testing Your Tap Water

Post by Graham » Wed Mar 04, 2009 6:55 pm

Chappie519 wrote:So using grahams liquor treatment calc here I would put 36 into the hardness box or the alkalinity box at the top? and that would be in CaCO3?
Yes put it in the alkalinity box. Sometime in the future I'll probably remove the hardness box or move it out of temptation's way to save confusion.

However, you have just about the ideal amount of alkalinity for pale ales, so it is mostly academic. You will not have to use any reduction stuff like CRS. You'll need to add some calcium though, and possibly a bit of magnesium for luck.

adm

Re: Alkalinity, Testing Your Tap Water

Post by adm » Wed Mar 04, 2009 7:10 pm

Question about the Hardness box, Graham....

I have a reliable figure for TA, (135 mg/l CaCO3) checked and double checked, but I also have a Total Hardness figure (145mg/l CaCO3) from my water company.

Should I just leave the hardness box at 0, or enter the figure into it?

The problem is that I don't have a separate Calcium, Carbonate or Magnesium figure from the waterco.... so if I just leave the hardness box blank, I end up with a unrealistic 0 for Calcium and Magnesium, and the Initial Ion Balance is 0.37:3.7 so indicates an impossible water composition.

If I plug the 145 figure into the Hardness box it works out a Ca number, and the Ion Balance looks more reasonable at 3.27:3.48

Then if I plug 2.5 into the Mg box, everything balances out nicely.....

So am I just fudging the numbers by putting the 145 into the hardnes box and then adjusting the Mg to get to balance?

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