Why is my betta fish biting his tail? Will a betta's tail grow back?

Thanks for reaching out about Stanley. First, test the water quality for pH, ammonia, nitrites and nitrates. Correct any problems. Laying on the bottom might be an indication of a swim bladder infection/fluid. These are commonly bacterial and systemic antibiotics required. A veterinary visit is needed to prescribe medications. Antibiotics added to the water are rarely absorbed, and are generally for skin infections, vis contact. 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 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.

Check the strength of the current created by the filter. Bettas do best in very slow moving water. A strong current can actually damage long finnage. Be sure to use a conditioner at each water change. My preferences are Prime, NovAqua, AmQuel Plus, StressZyme or StressCoat. You can find these in the aquarium section of the local Petco. You don't need to use all of them though. A bit of plain aquarium salt (NOT table or Epsom salt) can also aid in healing. Dissolve up to 1 teaspoon of salt per gallon of water and treat for 10-14 days then reassess fin condition.

Thanks for reaching out about Kai and including photos. It is difficult to determine is this is a full-thickness hole by the pictures. Tails tend to regenerate so monitor to make sure it doesn't get worse. Test and correct any water quality concerns. If other spots occur, testing for parasites by a veterinarian is recommended. Good luck.

This could be either a bacterial infection, such as Columnaris, or a fungal infection, such as Saprolegnia. It is difficult to say without an exam or image. Either can be treated with medications found in the aquarium section of the local Petco. Look for an antifungal or antibiotic. You may even find a combination product. Follow label directions carefully and remove the carbon filter insert during treatment. Maintain pristine water quality via filtration and regular partial water changes. If an antifungal does not work, try an antibiotic or vice versa. Keep water temp between 78 F and 80 F.

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.