here is a copy of something I wrote to sly in a PM. Enjoy!
"Muskies and other pikes belong to the more "primitive" fishes, so their swimbladders are connected to their guts (physostomous). That means to deflate it, they need to pass gas. So I think you're OK
Loaches have the same swimbladder condition. So my dojo loaches will swim to the surface every once in awhile to take a gulp of air, which they then swallow and force into the swimbladder. One of my loaches has a swimbladder disorder (and is a little retarded) so he doesn't fart enough. His rear end floats up, until he farts out a little bubble and then he sinks to the bottom."
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