How do I work out Alkalinity

[nobby]

My water report doesn't give the Alkalinity. So how do I work it out from my report ????

In the detailed report it give the Total Hardness as 53

Below is the sumary report.
...........................................................................................................

Hardness Clarke 9.275 Clarke
Aluminium <23.1 200 µg Al/l
Calcium 37.8 mg Ca/l
Residual chlorine - Total 0.65 mg/l
Residual chlorine - Free 0.60 mg/l
Coliform bacteria 0 0 number/100ml
Colour 0.567 20 mg/l Pt/Co scale
Conductivity 348 2500 uS/cm at 20oC
Copper 0.0227 2 mg Cu/l
E.coli 0 0 number/100ml
Iron <27.3 200 µg Fe/l
Lead <0.854 25 µg Pb/l
Magnesium 8.97 mg Mg/l
Manganese <5.34 50 µg Mn/l
Nitrate 2.33 50 mg NO3/l
Sodium 19.6 200 mg Na/l

[nobby]

Do you know I have a KH test kit that I use for my aquarium The KH of my water is somewhere between 0.75 and 1 so thats 40-50 CaCO3. Which I guess would be correct given that I have very soft water.

[nobby]

Thanks for that. Yes I got it correct KH or Carbonate Hardness is the Alkalinity and not normal water hardness. I have read about KH and GH though fish keeping and that did my head in