I am using a BB 6 gal with the NPT to 1/4 hose barb, the hose going to a class of water for an airlock. I checked on it this morning and found the water level in the hose to be at the same level as the water in the glass. If I lift the hose slowly and keep thy end still in the water, the water level in the hose stays even with the glass. When I put the hose back in the water, same result. This tells me that the pressure inside the carboy is equal to the outside.
The stopper/adapter/barb elbow were assembled wet with starsan. When I racked this to secondary, it was showing activity and pushing bubbles. Now if I give it a gentle rock, it pushes air down the hose, but then it equalized again.
Anyone seen this?