I was disappointed to find that there is very little mention of the bubbling, but the few things I found (advice to others who had witnessed this with their crabs and were alarmed and were seeking help) mentioned clear bubbles can mean he is too hot, too dry (neither of those true in our cage, which is about 73 degrees and 70-80% humidity most of the time), or too stressed. A brownish color to the bubbles, or a brownish leaking fluid can mean injury, and there is a good chance your hermie won't recover.
Well, Larry lost a leg within the next hour, then he just stopped moving altogether. He was still alive, but wasn't making any effort to move around. Next morning Larry was unresponsive, so we're taking his little carcass back to the pet store.
They get a new shipment tomorrow. Wish I had more options, but the other closest pet store is 50 miles away.
Thought I'd post this to get this info spread out a bit more since I couldn't find much myself on the net about it.
hope it helps someone.
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