Can betta fish tails shrink

Answer 1

They shouldn't, this is not normal. It is due to either finrot or physical damage. Finrot is caused by a bacteria (usually) or sometimes a fungus. These pathogens are opportunistic, meaning they attack fish that are already stressed or weak. The most likely cause is bad water quality. Make sure your betta's aquarium is warm enough, large enough (at LEAST 1 gallon) and maintenance is done frequently, especially if it is not filtered. Melafix or a little salt in the water will help the fins heal. If your betta is with other fish, nipping could be the cause. Many fish will nibble a betta's tail. The most likely culprits are danios, tetras and barbs and bettas should never be kept with these fish. Ideally bettas should be kept alone or in tanks containing only bottom feeders. Remove the other fish (or remove the betta to a separate tank) and treat with melafix. The other possibility is that the betta chews his own fins. They frequently chew in transit due to stress, but sometimes they do it constantly for no obvious reason. It's more common in fish that are kept in cramped or otherwise unsuitable conditions when they are young. I have a pet store cup rescue over a year old. He is a veiltail, but his fins are as short as a plakat's. As soon as they grow long enough for him to reach he chews them off again. He is in a large tank with decorations. Sometimes there is nothing you can do for fish that are psychologically damaged by poor treatment - they are only fish and are not adapted to cope with this sort of stress. Known fin chewers should not be bred as there is some evidence that the tendency to chew is hereditary.