Crikey! How big is that thing? (Couldn't find it in the post).
Would have been great if they let the single infusion mash go for 90 minutes plus mash-out so as the liquor contact time with the grain would have been the same. From our research here, this would have evened the pre-boil gravities up.
You'd want to make sure you didn't fall into the kettle when cleaning it
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