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Im not sure if this was a freak occurance, but it happened. The cuttle was in a custom made plexi section where no lip or cover was is present on the tank. I now have it covered with plastic egg crate.
They probably were chasing each other and one jetted a little too much in the wrong place...
if you are thinking of covering your tank, a lip around the tank will probably prevent this. you wont need an entire cover.