So, the bottom plate legs are about 3.5cm tall. Both the bottom plate and the grain basket plates have holes with a diameter around 2mm. Some pics below. Guess your helix will fit fine below the plate.
I always create my recipies for around 14l thinking I will lose a 1l to the boiler (trub). However, at the end of every brew I find it hard to leave that behind so I typically tip the boiler to take most of it. I'm 20 brews in and still can't decide if I should stop at tap level....after fermenting I end up leaving a fair bit of trub in the FV and can never decide if alot of that is what I transferred
. I will measure the vol of liquid below tap level next brew day and maybe leave that behind. Brews are fine so I'm fairly confident it makes no difference to my beer
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