White spots on betta fish are primarily caused by ichthyophthiriasis (white spot disease). This disease is triggered by a parasitic infection, characterized by white granular spots on the fish’s body, excessive mucus on the skin, frequent rubbing against the tank, lethargy, clamped fins, and a dull coloration.
Treatment Methods
1. Isolate Infected Fish: Separate the sick betta immediately to prevent the parasite from spreading to healthy fish.
2. Raise Water Temperature: Increase the aquarium temperature to 28–30°C (82.4–86°F) and maintain it steadily. This temperature range effectively kills the parasites.
3. Medicated Bath:
- Use a 2% methylene blue solution for a 6-hour daily soak until the white spots disappear, then continue treatment for an additional week.
- Alternatively, soak the fish in a 1% coarse salt solution for 20–30 minutes daily until fully recovered.
4. Water Changes: Change 30–50% of the water every 3–4 days to keep the water clean and prevent bacterial growth.
5. Tank Sterilization: Soak the aquarium with coarse salt for 30 minutes to eliminate pathogens.
Prevention Tips
- Maintain Water Quality: Perform regular water changes to avoid deterioration and buildup of toxins.
- Regulate Water Temperature: Adjust the tank temperature during autumn and winter to prevent sudden temperature fluctuations.
- Sterilize Equipment: Regularly disinfect aquarium tools and accessories to reduce the risk of bacterial or parasitic infestations.