Bren
As a Piscean i take offence to that
As you will well know Gastrointestinal Barotrauma is a common problem with divers, especually after a heavy DCI immunisation of Curry and Lager.
The prescribed cure is to release this gas using the most direct route, and unlike other gasses it is best to do this as quickly as possible.
However be carfull not to lose control nessesitating the use of the Warhammer Manouver (as covered in an old post), as this can get very messy if you are not prepared for it.
So if Divers can suffer from this why not fish? [Dr Nick? Sorry Dr Steve enters stage/screen left]
Dive Safe and Offgas whenever you get the chance,
Paul