Yeah I actually did dilute pre-boil. I took it above 27 litres (which was my target volume) to hit my numbers, then mixed it well and took another reading. When I got the pre-boil numbers right, I scooped out the excess to bring it back down to 27 litres. But like I say, something is amiss with my readings
As for my issue with US-05. It makes no difference if I re-hydrate the packets or if I just sprinkle them in, it always over ferments!
Is this just what US-05 does, or am I pulling too many fermentables from my mash? Should I mash nearer to 70°c next time?
Cheers