Thanks for the support! I may share another photo when I clean the ceiling. Nice reading supportive posts on this forum - it's a bit different to other forums I have used!
Without showing all of the carnage (I'm pretty embarassed), here is a part of it. The ceiling was indeed reached, and it's a high ceiling. I really don't have any idea how long the lid was off and I'm surprised that I slept through this explosion. I put the lid back on when I found it and...
I just did my first batch of all grain - everything went perfectly until I woke up this morning with the lid off my fermenter and mess all over the walls and floor. I have zero idea what happened. I am using a simple airlock with a float and cap that I filled 1/3rd way with boiled water. The...