I have the Guten same thing, almost. Even though it has a lock in screen the screen could lift when dropping the malt pipe into the kettle. Solution, secure it into position.
Any grain which is outside the malt pipe is there because it fell between the gap of the malt pipe and the kettle. When I stir the wort after the mash to take the PBG if I see any husks in there I just scoop them out, though it is very rare.
I am surprised there is so much debris in the bag pictured above, I would have thought the pump would have dumped anything floating around on to the top of the grain bed while the wort was circulating (had the bag not been there)
Also I can't understand the purpose of running the pump during the boil?
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