So, I decided to run a small batch experiment to play with water chemistry. I made two identical small batches back-to-back. The only difference being the water chemistry.
The recipe for both batches:
2 lbs american 2-row
2 oz c40
.25 oz perle hops for 60 minutes
2 grams of dry yeast - Safeale S-05 per Mr Malty
One gallon final volume of beer.
Batch 1 was straight tap water from my local municipality (Water One - Overland Park, KS). Batch 2 contains 37% RO water, 63% tap water, and I added one gram of calcium chloride to up the calcium and .3 ounce of acid malt to lower the PH. Determined this using the 2012 Water One quality report and the EZ Water Calculator spreadsheet.
Both batches received yeast at the same time and same temp. It has been three days of fermentation, and today I noticed that the krausen on the treated water batch is about 3 to 4 times bigger than the untreated batch. You can see it in the pic, below. The treated water batch is on the right.
I wonder if water treatment affects krausen or is this just the normal variation in fermentation? I plan on doing a side by side taste test once these are done fermenting and carbed up.