In another thread talking about a cheese called Cantal from "200 Easy Homemade Cheese recipes", I noticed something interesting in the ingredient list.
Recipes that use 4 gallons(16L) cow's milk
:3/4 tsp (3.75ml) calcium chloride dissolved in 1/4 cup (50ml) water.
Interesting datapoint. When last I checked, we put 30ml of CACL2 in a 100ml container and filled it with water to arrive at a 30% solution. Here's a recipe book that apparently a few people besides myself are using and it calls for 3.75ml dissolved in 50ml of water. I'm sure that will guarantee the 30% with a little buffer room. So what if the total volume of milk liquids is a little larger?
What that tells me is that I can keep my CACL2 dry and mix it fresh as I need it...3/4tsp (3.75ml) at a time for my 4 gallon (16L) cheese recipe. No muss, no fuss