Nottingham Water

Hi
I have downloaded the following info from Severn Trent for the water quality for my area. What treatment do I need to do to my water?
I currently only add a crushed campden tablet at present. Do I need to add Gypsum?

AnalysisTypical valueUK/EU LimitUnits
Hardness LevelModerately HardNo Standard Applies
Hardness Clark12.73No Standard AppliesDegrees Clark
Hardness French18.18No Standard AppliesFrench Degrees
Hardness German10.18No Standard AppliesGerman Degrees
Aluminium6.08200μgAl/l
Chlorine0.26No Standard Appliesmg/l
Coliform bacteria00no./100ml
Colour0.7620mg/l Pt/Co
Conductivity4112500μS/cm at 20°C
E.coli bacteria00no./100ml
Fluoride0.21.5mgF/l
Iron19.1200μgFe/l
Manganese2.2350μgMn/l
Nitrate20.750mgNO3/l
Odour0Acceptable to customers and no abnormal changeDilution Number
Pesticides00.5μg/l
pH7.586.5 - 9.5pH Value
Sodium19200mgNa/l
Taste0Acceptable to customers and no abnormal changeDilution Number
Plumbing Metals
Copper0.032mgCu/l
Lead0.6310μgPb/l
Nickel220μgNi/l

I have started doing Biab and thought it may help with mash efficiency. I have read that people add one tsp in the mash and one into the boil. I'm going to try this next brew and see what happens.

I will have a look into getting an analysis done, just wondered what others in my area had experienced?

These reports always look baffling! But a tiny fraction is useful for brewing and the rest just trumpets that it's ok to drink (and therefore the levels don't impact brewing). So begin by trimming it down:

All those "hardness" figures equate to:
73ppm as Calcium (...ions, note this is "as" calcium and doesn't mean "there is". It includes Magnesium and others).
pH7.6 (normally, can swing between 6.5 and 9.5).
Sodium; who knows? Haven't a clue what 192000mgNa/L relates too!
...and that's probably the sum of it.

Keep adding the campden tablet to be rid of any free chlorine.
Gypsum? Well a bit more Calcium wont do any harm, as for sulphate? I'd guess there isn't much sulphate so go ahead and try a tad of Gypsum. But can't say you need it.
Alkalinity would be useful but you are not told it! Nothing unusual there. However, alkalinity is often calcium bicarbonate and you can deduce there's not much calcium about so therefore not a lot of alkalinity to worry about.

10.18dh is equivalent to 181 ppm as Ca CO3 total hardness.
What you really want is the alkalinity as peebee says (as bicarbonate or as CaCO3) which will be a tad lower than the total hardness. You could get this by contacting the water company or , even better getting a salifert alkalinity testing kit..they are not very expensive.
You could also ask the water company if they test for Calcium (major importance), Magnesium, Sulphate and chloride, I assume their Sodium figure is meant to be 19mg/ltr.
The key one though is Calcium and based on total hardness as peebee says, the Calcium level should be 73 or a bit below given other ions are contributing to the total hardness figure. ...lets pretend its 65 (just for order of magnitude).
I've looked at the detailed report for Nottingham city on the web...and the summary doesn't show chloride and sulphate, but the detailed reports for each supply source do. This is non scientific, but if we take and average of the seeming 6 different supply sources the suphate av. is 45ppm and chloride is 50ppm...these are skewed up a bit due to one source being v high in chloride and sulphate.
If we say alkalinity is eg 170ppm ballpack as Ca CO3 (fits with moderately hard), magnesium is 10ppm (don;t know but its not so important) , Calcium is say 65ppm, sulphate is 45 ppm and chloride is 50.......then if we put that though the forum old water calculator it would suggest you might want to consider treating your water roughly as follows:

For mash and sparge water -
Pale ales/Bitter - 0.79ml CRS per Litre liquor.
Stout/Porter - 0.47ml per litre liquor.

If your mash water volume is 10ltrs (for BIAB??) then is recommends as follows:
Pale Ales: 2.8 grams gypsum to the mash, 2.8 grams gypsum in the boiler, 2 grams Epsom salts to the boiler.
Bitters: 2.8 grams gypsum to the mash, 2.8 grams gypsum to the boiler, 1 gram table salt to the boiler.
Stouts(&porters): 2.8 grams table salt to boiler, 7 grams calcium chloride to boiler.

I just add all my salts to the mash mixed in with the grain.

So basically you are stripping back the carbonates to get rid of excess alkalinity and adding extra calcium in form of Calcium sulphate for Pale ales and Bitters, and in the form of Calcium Chloride for Stouts. For stouts and porters you need less CRS acid solution because the roasted malts are acidic and do some of the job on their own.

Different water calculators will give different result, but all variations on the same theme.

Sorry this is a bit detailed but my mind needed a bit of exercise.