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**ajdelange** · 12-18-2011, 09:28 PM

Quote:

Originally Posted by gt541

I think the drops are of uniform size as the hypo needle is cut square to its axis (i.e. not sharp) with no burrs inside or out so surface tension should enforce consistency.

I'm not trying to convince you that they aren't - just throw some things out for you to think about.

Quote:

Originally Posted by gt541

The color changes are sharp and rapid. I also was under the impression that these indicators had very consistent pH transitions points.

Ummm. I'm color blind but when I look at the instructions for bromcresol green methyl red indicator used in alkalinity tests they say titrate to one color for one value of pH and another for another depending on which definition of alkalinity you are using. These would all look the same to me and even people with normal color vision have different levels of acuity. Also, the shapness of the calmagite endpoint depends on magnesium being present and on pH (a buffer is usually added to insure that the pH is correct) etc. In any event when you are using an indicator you are asking for a human to make a judgement and humans aren't always consistent in that. Fatigue, the color quality of the light being used to make the determination, the angle of subtense of the object being looked at all have an effect on how we perceive color. None of these may have an appreciable effect but in general an instrumental method is always preferred. With alkalinity you have the possibility of using a pH meter. With hardness you don't. There is an instrumental calcium/magnesium hardness test but the instrument is a sprectrophotometer.

Quote:

Originally Posted by gt541

The collaborative study is interesting, but one would need to be somewhat assured that all investigators had consistently good experimental technique.

In such a test you are measuring the method and the analyst. If a method gives a high CV intra lab then the chemistry itself is too variable. If it has a decent intra lab CV but a high inter lab CV then analysts are too variable (for this method).

Quote:

Originally Posted by gt541

I guess the cleanest method would be for me to carefully measure a water sample (multiple times to observe my own variation) and then have the same sample measured by an outside lab that would provide error bars about their measurements.

That's a good idea but it would be better if someone else put together the test sample without telling you what (quantitatively) is in it. Also, it should be made up with standardized chemicals (available from Hach and others) using Class A glassware dunked in a water bath etc. Quantitative analysis is a fascinating subject but there are lots of things to consider.

**triangulum33** · 12-19-2011, 05:24 AM

How do APA, IPA, and Belgian styles fit into Yooper's guide?

**emjay** · 12-19-2011, 05:36 AM

Quote:

Originally Posted by triangulum33

How do APA, IPA, and Belgian styles fit into Yooper's guide?

For the APA/IPA, the baseline should work pretty well, although the added sulfate in the guideline for British beers works well to accentuate the hop bitterness.

As for Belgian styles, it really depends on the specific beer, but the baseline should also work great in almost every case. Keep in mind that chloride tends to accentuate malt sweetness, while sulfate accentuates hop bitterness. If you're unsure what to do, just go with the baseline (it's referred to as the "baseline" for a reason

), and if you make future batches, you can adjust it with a tsp of calcium chloride or calcium sulfate if you think it might benefit, although the sulfate in particular is inappropriate in most cases.

P.S.: it was posted by Yooper, but it's AJ's guide

**triangulum33** · 12-19-2011, 05:48 AM

Thanks for dumming this stuff down for...umm....dummies!

**J8D** · 12-21-2011, 03:50 PM

Quote:

Originally Posted by Yooper

By Ajdelange

For British beers: Add 1 tsp gypsum as well as 1 tsp calcium chloride

[/QUOTE]

So using 100% RO water for a British beer, I am adding 1 tsp of gypsum and 2tsp of calcium chloride per five gallons of water plus +1% sauermalz? Just want to make sure before I hit the LHBS. Thank you.

**ajdelange** · 12-21-2011, 03:54 PM

No. 1 tsp gypsum and 1 tsp calcium chloride (per 5 gal treated). Plus the sauermalz - 1 % of the total weight of the other grains.

**J8D** · 12-21-2011, 04:10 PM

Thank you!!!!!!

flabyboy · 12-21-2011, 06:51 PM

Does anybody on here add NaCl or table sugar as a salt addition. My water profile in low on NA and CL, but is pretty high on calcium and sulphates. Thought it may be a good way to up the levels I need, but not sure how much to add because the calculators out there don't have it included

**ajdelange** · 12-21-2011, 07:03 PM

They don't? Are you sure about that?

Anyway you start by determining the amount of NaCl you propose to add to each liter. If you are going to add 1 gram per gallon the amount per liter is 1000/3.7854 (1000 milligrams per gram, 3.7854 liters per gallon). Now convert that to millimoles/L by dividing by the molecular weight of sodium chloride, 58.44 mg/mmo, so that 1 gram/gal is 1000/3.78534/58.44 mmol/L. Each millimole of NaCl contibutes 1 mmol of sodium and one of chloride. To get the weights you multiply by the atomic weights of, respectively, sodium and chloride ion. One gram per gallon contrubutes
22.99*1000/3.78534/58.44 mg/L sodium and
35.45*1000/3.78534/58.4 mg/L chloride

mabrungard · 12-21-2011, 10:20 PM

Quote:

Originally Posted by flabyboy

Does anybody on here add NaCl or table sugar as a salt addition. My water profile in low on NA and CL, but is pretty high on calcium and sulphates. Thought it may be a good way to up the levels I need, but not sure how much to add because the calculators out there don't have it included

You're using the wrong calculator. Bru'n Water has table salt in it because I like to use it on occassion in limited quantity.