Originally Posted by the_bird
If she asked you for a glass of water, would you fill a glass from the faucet?
Unless you wouldn't drink the water straight out of the tap, I can't imagine there's any reason to boil the water. Do what you want to do, but strikes me as massive overkill.
This is true. If she were to drink all 5 gallons of water in a day, there'd be no worries. But it will take months to go through 5 gal of soda water.
Take a water bottle, starsan it if you'd like, and fill it with tap water. Wait 1 month. It will taste awful, and quite possibly start visibly growing things. I've seen glasses of tap water start molding after mere weeks.
The problem is, your pipes, your faucet, and especially your faucet aerator still harbor bacteria. Also, Starsan only sanitizes, it doesn't sterilize. Sanitize means massive reduction of bacteria, but not elimination. Even small colonies can grow into big ones if given time. By transferring at boiling temps, then putting it on CO2, the water only sees a sterile environment after it cools, so chances of infection approach 0.
Plus it takes 15 minutes, and I can do it while I'm mashing a batch of beer.