While making my first batch, the directions said to make my wort 3 gallons. After my boil it said to chill the wort down to 80 degrees before pinching. This can be accomplished by adding 2 gallons of cold water to my wort to make a 5 gallon batch. Is this normal? I was so paranoid to add cold water because of contamination, so I boiled the 2 gallons of cold water to sanitize it before adding it to my wort. By doing this, it took a little longer to chill my wort. Can I add cold water to my finished wort before putting in the yeast? Or is this bad technique. I don't want to contaminate the beer. Please help.