Mantis shrimp in there (or not?)

[justinl]

Do you ever get missing hermits/snails or their busted shells? If so then yes that would lean towards a mantis. A visual is of course the only solid evidence. Clicking alone is not hard evidence because more often than not, it ends up being a relatively harmless pistol shrimp. Or on the odd occasion a snail that is in front of a powerhead and is having its shell banged against the glass.