also i read this........
The first treatment would be to fast the fish for 3 days solid. This will allow your betta's digestive system to purge and process, hopefully clearing his system and allowing the pressure to diminish on his swim bladder, therefor allowing the swelling to go down. Even if this is not due to constipation it will not hurt just to prevent any added pressure to his swim bladder. If at the end of the three days he is still not better, he may require an even longer time to allow the affected swim bladder to recover. Do not worry about your betta going days without food. As long as he was well-fed previously before he will do fine and won't starve. Now at the end of the fasting period, feeding a completely thawed, deshelled, and mashed up pea can have great affects on further cleaning out a bettas system especially those with constipation. Feeding a bite sized piece on a blunt toothpick works well, patience is everything when trying to get bettas to accept it. Daphnia, which is a live or frozen food, can also be fed to your betta once his fasting is over and will act as a laxative as well.