I've obtained details of my water quality from the water co., but it doesn't appear to cover all of the values listed in the Bru'n water spreadsheet:
Sodium: 28.81mg Na/l
Calcium as CaCO3: 85.42mg/l
Iron: 21.30 ug Fe/l
Sulphate: 63.62 mg SO4/l
Chloride: 28.86mg Cl/l
Nitrate as NO3: 06.62mg NO3/l
Fluoride: 0.43mg F/l
Alkalinity as CaCO3: 55.52 mg CaCO3/l
We do not measure for Potassium, Bicarbonate or Carbonate within the supply.
They also appear to have not included the Magnesium value. I have seen that, reading the comments on the spreadsheet that Carbonate and Bicarb values can be estimated, and Potassium ignored.
I have a value from when they provided this last year (there have been measured variances from last year on other values) This was 25.42 mg/l as CaCO3, and Calcium 90.19 mg/l as CaCO3 (most values are slightly down on last year, only nitrate is up).
How big an issue is the missing Magnesium value? Could I use last year's figure and not end up way off with my additions/pH?