300mg/l CaCO3, or very hard.
To get it down to 20mg/l:
For light beers this means 1.5ml of CRS per litre of liquor.
Less for dark beers, maybe 1.2ml.
1 ml of CRS will remove CaCO3 at the rate of 183 ppm per litre of water.
Just did a test of my tap water and got a reading of 128ppm CaCO3.
2 other tests done a while back showed my calcium at 100ppm.
I bought a salifert KH/ALK Carbonate Hardness/Alkalinity test kit on ebay.
The kit measures the alkalinity and expresses it in value's,
dKH (degree's karbonate hardness) and Alkalinity in meq/L.
You take the meq/L number and multiply by 50 to get a ppm/L CaCO3 reading.
Or get a better test kit :D
Any chance you've tested this lately? Still waiting on my water test kit.
Cheers. [smiley=thumbsup.gif]
Do you remember what the TOG water was ?
I take it you would prefer 100-150 region.