The need for nighttime lighting for betta fish requires careful handling, with specific recommendations as follows:
Controlling Lighting Duration
Betta fish should have 6-8 hours of light per day, and young fish can have this extended to 8-10 hours. However, leaving the lights on continuously for more than 12 hours can disrupt their biological clock. A dark environment should be maintained at night to simulate the natural day-night rhythm.
Impact of Nighttime Lighting
Negative effects: Strong nighttime lighting significantly increases stress responses in betta fish, potentially raising their mortality rate by 40%. An environment lacking sufficient darkness can also boost their aggressiveness by 40%.
Exceptions: During the breeding period, lighting can be extended to 16 hours, and UVB lamps can be used to improve fertilization rates.
Recommendations for Lighting Selection
Intensity: The recommended light intensity at the water surface is 200-500 lux (equivalent to indoor natural light).
Color temperature: Use 5000K cool white light during the day to promote activity, and switch to 3000K warm light at night to aid sleep.
Installation method: The light fixture should be 15-20 centimeters above the water surface and positioned at a 45-degree angle for illumination.
Common Misconceptions
Avoid direct sunlight or high-intensity light fixtures, as they can cause discoloration and white spot disease.
A completely dark environment is also unfavorable; it is advisable to maintain 2-4 hours of low light daily.