I'm using beersmith which calculates brew house efficiency, it takes everything into account, mash efficiency, dead space in mash tun and kettle, and adding your measured OG effects it also.
I use pellet hops.
It's a 2.5 gallon batch, and I got the correct amount of wort.
I'm using my equipment that I use for 5 gallon batches, I bet the dead space effects the smaller batches more.
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