Just brewed an extract beer. 6.6lb of light LME, 2lb of Amber DME, assorted hops etc. My calculations say I should have an OG of 1.056ish, but I'm ending up with 1.035. What's up with that? It was a 3gallon boil, topped off to 5 gallons. I measure the temp at 20 centigrade which is what my...