Why does my betta fish have a hole in its tail? Is it serious?

Thanks for reaching out about Kai and including photos. This could be a solitary Ich lesion (which is unusual, as there are usually multiple) or a hyper-active mucous gland. Check water parameters for pH, ammonia, nitrites and nitrates, correcting any problems. If more lesions appear, a veterinary visit can help with a diagnosis through a microscopic examination of a skin scrape, and therefore prescribe the appropriate treatment. Good luck.

Thanks for reaching out about M.S. First of all, check water quality for pH, ammonia, nitrites and nitrates, correct any problems. Poor water quality can lead to dermal changes/irritations that can results in tattered scales or fins, and other dermal lesions. If the lesions progress, a veterinary visit is needed to assess and provide a diagnostic/treatment plan. Any of the over-the-counter medications to add to the water, rarely improve conditions but will more likely be a detriment to water conditions. Good luck.

Thanks for reaching out. Fish heal pretty well but depends on the gape in the skin. But the important part is keeping the water as clean as possible, to decrease contamination of the wound. Make sure the nutrition level is high (fresh food). If the wound becomes angry or you notice white fluffy lesions (likely fungus), seek an examination with a veterinarian. If the wound is wide, seek a veterinarian sooner. Good luck.

Thanks for reaching out about Inferno and including photos. Have you tried contacting local fish clubs or koi clubs for suggestions of a veterinarian? Test and correct water parameters. Sub-optimal water quality, nutritional deficiencies, bacterial infections, parasitic problems are the most common. By the photos, he appears slightly thin and scales dull. Vitamins and nutrients degrade in fish food rapidly, so should be re-purchased every 3 months. A skin scrape and microscopic examination at a veterinarians office should provide answers to skin parasites and possible infections, then a treatment plan can be implemented. Good luck.

Thanks for reaching out about Gummy. Not sure of biting the tail is normal, especially if chewing to the point of removing part of the tail. Itching or irritation are most likely. Test and correct water quality including pH, ammonia, nitrite and nitrates. These can be dermal irritants. Bacterial or parasitic concerns, spinal problems (scoliosis due to vitamin C deficiency) are also common and a veterinary visit would be needed to assess and provide a diagnostic/treatment plan. Good luck.

Thanks for reaching out about your fish. Water quality or aggression by other fish should be considered. Testing water quality for pH, ammonia, nitrite and nitrate, correcting any problems. The fins should re-grow is the problem is corrected. Good luck.

Thanks for reaching out about Ember and including photos. Not sure if any lesion are recognized. If concerns continue, a veterinary visit is recommended for a possible skin scrape and microscopic exam. Maintain pristine water quality and provide a good diet. Good luck.