O.G. Problems, help me figure this S%$# out

About the only thing SGT Stogie forgot to add was; "Drop and give me 20."

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One easy check to see if you're leaving sugar behind after the sparge is take a small pinch of wet grains and suck the juice. It should be as bland as unsweetened oatmeal. If not and it tastes sweet...then you're leaving gravity points behind.

 

I just assumed he drained the mash tun before adding the additional two gallons of what would be 'sparge water'. My bad. Great advice in here. Go forth and brew again!

 

What everyone else said is worth paying attention, but I wonder about your thermometer. How cold is your grain when you add the strike volume? I keep my grain in the garage and even in the winter, I would never need to go as high as 180 to hit 154. Every system is different, but I brewed last weekend and with 10 pounds of grain and my strike water was ~3.5 gallons at 162 this got me to the target of 150. I don't know if this could be related, someone else can answer the science question of what happens to efficiency when your mash temp is too high, but that would be something I would check if I were you.