Betta fish cannot be directly kept in untreated tap water, but tap water that has been exposed to air (for chlorine removal) or treated with a dechlorinator is suitable for raising bettas. Below is a detailed analysis:
Betta Fish's Water Quality Requirements
Basic Adaptability: Betta fish are not extremely demanding when it comes to water quality—they are relatively hardy ornamental fish. However, sudden changes in water quality must be avoided.
Key Parameters:
pH Level: The optimal range is 6.5-7.2; slightly acidic to neutral water is most suitable.
Water Hardness: There is no need to deliberately pursue soft water. The hardness of tap water after regular air exposure usually meets bettas' needs.
Temperature: As tropical fish, bettas require a water temperature between 25-28°C (77-82.4°F). Heating equipment is necessary in winter to maintain a stable temperature.
Effects of Tap Water on Betta Fish
Risks of Direct Use: Freshly drawn tap water contains chlorine (used for disinfection), which irritates the mucous membrane of bettas' gills and can lead to diseases like fin rot and enteritis. Low temperatures also reduce the fish's immunity, triggering infections such as water mold.
Harm from Water Quality Fluctuations: The temperature difference between untreated tap water and the water in the fish tank may exceed 2°C (3.6°F), easily causing bettas to experience stress responses—such as staying at the bottom of the tank or refusing to eat.
Correct Ways to Use Tap Water
Air Exposure Treatment:
Time Requirement: Let the tap water sit still or be exposed to air for 2-3 days to allow chlorine to evaporate naturally.
Operation Tip: Use open containers (such as buckets or basins) to increase the evaporation surface area and speed up chlorine removal.
Rapid Dechlorination Methods:
Dechlorinator: Add specialized dechlorination products (e.g., "Yu Le Bao" dechlorinator) according to the instructions. This method is suitable for situations where water changes are needed urgently.
Aeration Treatment: Use an oxygenation device to accelerate chlorine evaporation—24 hours of aeration can achieve the same effect as 2-3 days of air exposure.
Water Temperature Adjustment:
Temperature Difference Control: When changing water, the temperature difference between the new tap water and the tank water must be ≤ 2°C (3.6°F). Use a thermometer to ensure safety.
Winter Insulation: Use a heater to maintain a stable water temperature and avoid large day-night temperature fluctuations.
Precautions for Raising Betta Fish
Regular Water Changes: Replace 1/3 of the tank water every week to keep the water clean and reduce the accumulation of ammonia and nitrite.
Water Quality Monitoring: Use test strips to regularly check the pH level and ensure the water quality remains within the suitable range.
Tank Space Configuration: The tank capacity must be ≥ 3 liters (0.79 gallons) to prevent water quality deterioration caused by a small water volume. A simple filtration device (such as a sponge filter) can be used to maintain water quality.
Disease Prevention:
Behavior Observation: Check the condition of the betta's fins, the brightness of its body color, and its eating habits daily to detect early signs of diseases like fin rot and ich (white spot disease).
Emergency Treatment: If a disease is detected, immediately raise the water temperature to 30°C (86°F) and add salt at a concentration of 0.3% (3 grams per liter of water). Observe the treatment effect for 3-5 consecutive days.
Environment Optimization:
Aquatic Plant Configuration: Plant shade-tolerant aquatic plants such as hornwort and water lettuce. These plants not only purify the water but also provide hiding spaces for bettas.
Decoration Selection: Avoid using decorations with chemical coatings (such as colored pebbles) to prevent toxic substances from leaching into the water.