Originally Posted by BigKahuna
well, the easy answer is "Don't worry about it." It will be what it will be. You will make beer. And now isn't the time to worry about anything other than sanitizing your fermenter.
Worry about process and or efficiency when you have numbers and details from your first batch.
Good advice, get your first one out of the way and run some numbers. I started AG adding a pound if base malt (advice from here), I am 5 batches in and the best I have ever done is 61%. I just put the 5th batch in the fermentation chamber to cool some more before I pitch ( gotta love 89 degree FL ground water), so I will measure that in a couple of hours. I have made changes to mash volume, batch sparge technique, and sparge temp. The last 2 batches I started diving into water chemistry (water primer in brew science is priceless) and all I have to say is if you gave poor efficiency, check the crush first. The first 4 batches were from the same online vendor that claims "the best crush ever", the 5th batch is from another online vendor (also well respected here) and the crush looked amazingly better.