crs then campden tablet?

[timbobist]

Just got my salifert test kit today, did a sample test of my water which gave me a result of 188mg/l so I times this by 30l of brewing water which equals 5640 divide by 183 equals 30.8ml of crs to be added. Do I need to test the water before adding a campden tablet or after? Also do u think I need to add some gypsum to the mash water and the sparge water or one or the other or neither? Cheers guys help much appreciated.

[GrowlingDogBeer]

Whether you test before or after the campden tablet won't make any difference.

However, you are saying your alkalinity is 188mg/l

What are you trying to reduce it to, as 1 ml of CRS reduces the alkalinity by 183mg CaCO3, so by adding 30.8ml you will reduce your CaCO3 level down to about 4mg/l CaCO3 which seems too low to me.

I don't know what else you need to add as you haven't told us what your existing levels are.

Where are you located then someone local may have a good idea as they may share your water.

[timbobist]

I am trying to brew a pale ale, never done water treatment before but trying to reduce alkalinity to 25mg/l I live in Bedford, quite a hard water area. I thought my calculations would bring alkalinity down to 25mg/l? Not 4 where did I go wrong?

[GrowlingDogBeer]

I was wrong with my guess at 4, actually you would been reducing to zero now I have a calculator ready to hand.
Your calculation just removed all of the CaCO3, you forgot to leave 25 behind, You forgot step 2 and 3 below.

The way to work out CRS adjustment is.

1. Take your "current" reading, in this case you have 188mg/l CaCO3 in your water
2. Subtract your "target" level, in this case 25mg/l CaCO3
3. The amount you need to remove is ("current" minus "target") or (188-25) = 163mg/l
4. Multiply the amount you need to remove by the total liquor, which in your case is 30l (163 x 30) = 4890
5. We know that 1ml CRS reduces Alkalinity by 183mg, you need enough CRS to remove 4890, so 4890/183 = 26.7

Therefore you need 26.7 ml of CRS to reduce your 30l water from 188mg/l CaCO3 to 25mg/l CaCO3

Without knowing anything else about your water I'd be inclined to add a teaspoon of Gypsum to the Mash and one to the boil, not sure why, just seems to be what people do.

There is more info about water treatment here in the Brewing Knowledge Base

http://www.jimsbeerkit.co.uk/home_brew_ ... atment.htm

[timbobist]

Thanks for the info mate I knew something was wrong with my calculations but wasn't sure what, I am going to try and find a bit more out about my water from the anglian water web site to are if that helps

[fisherman]

If I was making a pale ale with your alkilinity I would use camden then .87 ml of CRS per litre of water used for a 23 litre brew . And 7 grms of DLS per litre . Half mixed dry in the dry goods and the rest in the boil. Should come out fine.
good luck

[WallyBrew]

And 7 grms of DLS per litre ................................ Should come out fine.
good luck

[fisherman]

Sorry .7 grms Whoops

[rossi74]

Whether you test before or after the campden tablet won't make any difference.

i was just looking for the answer to the same question and noticed in a section in the brewniversity saying campden tablets will alter alkalinity.

The usual recommendation of 1 Campden tablet per 20 (US) gallons (~77.5l or 17 UK gallons) is intended to deal with a worst-case scenario of 3mg/l chlorine as chloramine. This would add 1.9mg/l of sodium; 3mg/l of chloride, 8mg/l of sulphate, 1.5mg/l ammonium ions and the alkalinity would be reduced by 4.2mg/l as calcium carbonate.

or is this too smaller amount to realy be concerned with?

cheers kyle