Yeah its definitely under 1/2". I cleared some foam so I could get the lid back on. Reinstalled the airlock and it's back to bubbling so I think it'll be ok
I came home at lunch to find my airlock flooded and foaming at the top. I changed it to a blowoff tube and came ho.e at the end of the day to a bucket with no lid and a tall foam cap. Do I just scrape off the foam and replace the lid?