....As you start to dive you need to in fact add more air to your BCD so that you can remain neutrally buoyant. This is because every 10 meters (33ft) the air compresses by half. So all that air you had makes you neutrally buoyant at 33ft, is now compressed to half of its original volume at 66ft. Consequently it does not do its' job of keeping you neutrally buoyant, now you are negatively buoyant and you may need to add air counter balance. The reason this is so important is to save valuable energy. Fish have to live on only what they eat, and sometimes meals are few and far between. By having a properly regulated swim bladder, they can save valuable energy by not having to regulate depth manually by swimming. They don't have to fight to stay at the depth they want.
....Unfortunately when they are brought up from any depths of consequences, they are not able to excrete the air in the bladder fast enough. Rock fishing is the best example of this, as you regularly see the organs distended and coming out of their gullet and their eyes popping. Basically they are getting a really bad case of the BENDS. If a fish at 33ft deep has a half full bladder of air, if they are brought up to the surface their volume of air in their bladder would have doubled in size, now it is full. So full isn't a terrible thing, they haven't popped anything, but if they are not allowed to return to the depths and let the bladder be compressed, it could be a problem. That full bladder at the surface will not allow them to be neutrally buoyant, they will float and they probably will not be able to right themselves. This may mess with their equilibrium and may put unnecessary pressure on vital internal organs. That is why fish caught from any sort of depth may be upside down in the tank and not able to swim right side up..Also a lot of times they will die from this, and we all know how crucial a 10% penalty may be in these tournaments.
Bass with 'the bends': bass brought up from deeper water suffer from an expanded bladder and will probably die unless the bladder is deflated.
....I 'pop' any fish I am going to keep in a well, at any depth over approximately 25 ft. I usually do this fairly soon after a fish is in the tank, if not immediately. “Popping” is fairly easy to do; all you need is a hypodermic needle (I know this is harder to get than it sounds.) I use an 18-gauge 1.5-inch needle. The bigger needle makes it easier to penetrate through the tough scaly skin. Also the larger gauge makes it easier for the air to escape quickly.
....Getting control of the fish is a tough step, because you must be firm but you do not want to cause trauma to your fish. What I like to do is get a good grip of the fish. I recommend pinning them against the side of the tank, so that your hands are wet and you will minimize the amount of slime coat and scales you will take off. Get the fish on its side and fold the pectoral fin against its side. The easiest way to do this is to insert the needle approximately about 2/3rds of the way down the fin, along the dorsal (top) edge.
The operation begins... By placing the bass on a smooth, flat surface. This will alow you more control when performing this proceedure.
Proper placement: the needle seen here enters at a shallow angle underneath the scales rather than through.
....You want to try and enter the skin at a shallow angle so that you can go underneath scales rather than through them. They are the fish's armor coating and are very strong and tough to puncture. Once you go through the skin you usually only need to go between a ½ inch to 1 inch, depending on size of the fish to access the bladder. Think about how thick fish fillet usually are, almost definitely under an inch for most bass.
