Graham's water calculator help please.

[jubby]

At the risk of starting another water treatment thread, I have a question on the use of Graham's water calculator.

My water composition is as follows:

Sodium 11, chloride 22, Sulphate 30, Calcium 110, Magnesium 2.4, Alkalinity 234 CaC03. All as mg/l

I can enter all this info into the calculator and it will indicate CRS (or boil) only is required. I have been brewing with CRS only with good results, but it would be good to know that I am using this calculator correctly.

After entering all the above info, if i change the 'target liquor' from automatic to bitter or pale ale, lots of additions pop up in the bottom table, these are:

Gypsum, Calcium Chloride, Magnesium Sulphate.

Anybody know what's going on here? Am I using the calculator correctly?

I use an Imac with firefox 3 if that makes any difference.

[Graham]

To select the target water for bitter, you are implying that you want to change your water composition to something else. Those additions match your domestic water to your target water.

As it happens, by using CRS you will have just about enough calcium for things to be okay, and you could get away without other treatment. If you boiled your water, however, you would be deficient in calcium. If your mash pH is okay you are probably okay.

[jubby]

Thanks Graham.

I understand your point about Changing my water composition to suit a region, such as London or Burton, but i don't understand the types of ale in the list. Stout, porter bitter etc. I assumed for instance, that when brewing Old Peculiar which I would describe as a porter, I would need no additions other than CRS because I had the target water set to automatic. Should I have it set to 'porter' and make additions which may improve the brew?

I must add that my mash ph was spot on when I was using unfiltered tap water, CRS and camden tablets. I then fitted a carbon filter to my water supply to remove chlorine, flouride and heavy metals. (alkalinity remained the same at 234mg/l CaC03) Since then, my mash ph has always been a little low. (4.8 to 5) I have added half a camden tablet to the mash liquor of my most recent two brews and both of these have been spot on 5.2-5.4. Don't understand that, possibly coincidence, but that's probably another thread.

[Graham]

Thanks Graham.
I understand your point about Changing my water composition to suit a region, such as London or Burton, but i don't understand the types of ale in the list. Stout, porter bitter etc. I assumed for instance, that when brewing Old Peculiar which I would describe as a porter, I would need no additions other than CRS because I had the target water set to automatic. Should I have it set to 'porter' and make additions which may improve the brew?

The composition given for the water types and the beer types in the drop-down list are just generally-accepted mineral levels that others think appropriate for different beers. I do not necessarily agree with them because they are different depending upon where you look, and because many of these figures are based on historical assumptions that are not relevant today. They are just generalisations anyway. It is far more important, in my view, to ensure that the pH of the mash is correct and that there is sufficient calcium for other things to function properly.

If you have no issues with the quality of your beer, I would not worry unduly about it and just leave the target water set to all zeros.

There is some information about water mineral levels in the table at the very bottom of this page.
Murphy's water page.

The "Automatic" means something else, and is not that automatic. It is described in footnote 5.

[jubby]

Thanks again Graham, I will stick with just CRS.

[jubby]

I might give that a go with my next brew, thanks Chris. Why the calcium chloride for maltier beers?

[jubby]

Thanks Chris.