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What kills betta fish?

Betta fish, also known as Siamese fighting fish, are a popular pet choice due to their beautiful fins and vibrant colors. However, they require specific care to thrive. Understanding the most common causes of betta fish death can help owners provide the best possible habitat.

Water Quality

Water quality issues are the number one killer of betta fish. Bettas are adapted to live in small bodies of water with minimal water flow. This makes them especially sensitive to water chemistry changes. Several water quality factors impact betta health:

Ammonia and Nitrites

Betta fish produce ammonia as a waste product. High ammonia levels burn gills and poison fish. Nitrites are also highly toxic. Both chemicals should be undetectable in a cycled tank. Perform regular water changes and test water parameters weekly to control ammonia and nitrites.

pH

Bettas prefer a pH between 6.5-7.5. pH outside this range stresses the immune system and damages organs. Monitor pH and make adjustments with chemicals or substrates if needed. Peat moss lowers pH while crushed coral raises it.

Hardness

Bettas thrive in soft water with a hardness between 5-15 dGH. Hard water can form mineral deposits on betta gills. Aim for a hardness around 10 dGH. Use purified water or a commercial conditioner to reduce hardness if needed.

Temperature

Bettas are tropical fish that require warm water between 75-80°F. Temperatures below 74°F compromise the immune system. Use an adjustable heater and thermometer to maintain a stable temperature.

Tank Size

Bettas require a minimum tank size of 5 gallons. Anything smaller causes chronic stress from ammonia buildup and lack of exercise. Aim for at least a 5-10 gallon cycled, heated, and filtered tank. Perform weekly 25% water changes.

Lack of Oxygen

Bettas have a special labyrinth organ adapted to breathe oxygen from the surface. However, this does not eliminate the need for dissolved oxygen in the tank water. Ensure the tank is not overstocked and has surface agitation from a filter or air stone to maintain oxygen levels.

Jumping from Tank

Some bettas are prone to jumping out of open tanks. Use a tight-fitting lid with just a small gap for filter and heater cords. Water should reach close to the top of the tank, within 2 inches from the lid.

Diet

Feeding issues lead to malnutrition, bloating, and constipation. Offer a high quality betta pellet or flake 2-3 times per day. Give just enough food for the betta to consume within 2 minutes. Supplement with frozen or live foods like brine shrimp or bloodworms twice a week. Avoid overfeeding.

Injuries

Tank decorations and aggressive tankmates can injure betta tails and fins leading to infection. Use soft silk plants instead of sharp plastic decor. Do not combine male bettas or fin-nipping species like tiger barbs in the same tank.

Stress

Chronic stress weakens the immune system of bettas. Causes of stress include inappropriate tank size, lack of hiding spots, harassment from tankmates, and frequent handling. Minimize stress by optimizing tank conditions and limiting disturbance of the tank.

Diseases

Common betta fish diseases include:

Fin Rot

Fin rot presents with frayed fins and greyish patches. It is caused by bacteria opportunistically infecting already-damaged fins. Improve water quality and use antibiotics to treat fin rot.

Velvet

This parasitic infection coats bettas with a gold-dust appearance. It spreads rapidly and can kill within days. Velvet is treated with copper medications.

Ich

Tiny white specks resemble salt grains on infected fish. The parasite detaches and falls off fish into the water to multiply. Raise temperature and use ich medication containing malachite green or formaldehyde.

Swim Bladder Disorder

Bettas float sideways or struggle swimming if swim bladder inflation is disrupted. This is often caused by constipation from overfeeding. Treat with Epsom salt and fast for 2-3 days.

Dropsy

Extreme bloating causing raised scales and a pinecone appearance. It is a symptom of organ failure rather than a disease itself. Unfortunately, dropsy is difficult to cure once symptoms appear.

Columnaris

Fast-moving bacterial disease causing visible grey/white patches on skin and fins. Treat with strong antibiotics at the first signs of infection.

Old Age

With excellent care, bettas typically live 3-5 years. Their lifespan maxes out around 7-10 years. Bettas gradually become weaker with old age. Make sure older bettas can easily access food and the water surface.

Preventing Betta Fish Deaths

The best way to avoid untimely betta deaths is focusing on prevention:

  • Maintain excellent water quality with regular testing and changes
  • Select young, healthy bettas free of disease
  • Feed a varied diet tailored to betta needs
  • Provide at least a 5 gallon cycled and heated tank
  • Add hiding places and avoid tankmates that nip fins
  • Minimize tank disturbances and handling stress

While bettas are hardy fish compared to some species, they do require specialized care. Recreating the warm, stable water conditions they evolved for allows bettas to thrive in home aquariums.

Conclusion

Betta fish have a reputation as an easy starter fish, but they are more delicate than their hardiness suggests. Understanding the most frequent causes of betta death equips owners to anticipate and recognize issues early on. With vigilance and prompt treatment, most betta health problems can be successfully resolved. Providing the proper tank size, clean water, nutrition, and low stress environment rewards betta owners with a brightly colored, graceful fish.