Betta fish are fascinating creatures with highly powerful vision that they rely on to survive in their natural surroundings. Their sharp eyesight helps them locate prey and navigate their environment, using well-developed sensory organs. However, poor lighting conditions, such as at night, can pose challenges due to drawbacks in their vision.
Understanding their behavior, temperament, and dietary needs through thorough research is key to maintaining a happy and healthy pet.
Let’s find out how the betta eye works, how their vision is affected by sunlight, daylight, and night, and explore more about their needs!
How Is the Betta Eye Different from The Human Eye?
The eyes of a betta fish are remarkable and serve as a crucial tool for their survival in their natural habitat. As carnivores, they rely on their eyesight and specialized sensory receptors to detect and hunt their target.
Unlike humans, who have binocular vision, bettas possess monocular sight, meaning their eyes can move independently and view opposite directions simultaneously. This feature expands their visual area, helping them spot potential food or threats more effectively. However, this adaptation comes with a trade-off, as they struggle to focus both eyes on a single object.
The betta’s vision is supported by retinas equipped with rods, which are better suited for detecting motion rather than sharp detail. This makes them efficient hunters in dim conditions, but their limited ability to focus affects precision. Having observed these unique species closely, I’ve come to appreciate how their evolutionary traits make them such effective predators, even if their abilities differ greatly from the human eye.
Their specialized sight allows them to thrive, but it also highlights the balance of advantages and limitations in their design.
Do Bettas Have Different Eye Shapes and Vision Abilities?
The pupil of a betta fish is unique compared to mammal eyes, such as those of humans, as it remains fixed and cannot autofocus or refocus. Because of their limited spatial vision, bettas rely on sunlight to navigate their surroundings and locate food. Without natural light, they depend on artificial lights to fulfill their basic needs. Unlike nocturnal animals, their cornea has not evolved to utilize many rods, making them more active during daylight rather than in the dark. Bettas are also surprisingly good at differentiating hues, an ability superior to that of humans, enhancing their capability to recognize subtle color changes.
Their monocular eyesight allows each eye to work independently, but this makes it difficult to notice objects or prey that are far away. Despite this limitation, their evolution has favored other traits, such as heightened sensitivity to color perception. As a tropical species, bettas are adapted to environments with abundant natural light, making them less reliant on photoreceptors commonly found in nocturnal animals. With their vibrant colors and dynamic vision, these energetic fish thrive in bright conditions, aided by features like sensitivity to LEDs and their specific position in their environment.
Can Bettas See in The Dark?
Betta fish are known for their beauty, but their ability to see in darkness is quite limited due to their poor vision. The primary reason for this is the slow functionality of their iris, which cannot quickly adjust to changes in lighting. While humans and many other creatures have eyes that are better adapted to night conditions, bettas rely on natural sunlight during the day to find food. Their tiny iris struggles to control the amount of light it receives, leaving their vision blurred or even rendering them temporarily blind in complete darkness.
When you turn off the lights in their aquarium, their eyes adjust so slowly that it can take minutes—sometimes the same time it takes the sun to set, about 30 to 60 minutes—for them to recover. This can be a frustrating and even scary experience for these delicate tropical species. Because they are not nocturnal animals, they have not adapted to survive without light during extended periods of the day-night cycle. Instead, they depend on sunlight filters through water columns, even in relatively murky environments.
To support your betta’s unique needs, you can plant extensively in their tank. This approach creates a stress-free, secure habitat with a mix of shade and diffused sunlight, allowing the fish to feel safe and comfortable. The various regions of the tank help their eyes adapt effectively to bright light and prevent harm or impairing their vision. This not only improves their environment but also helps them adjust more naturally to lighting changes.
Fun Fact: While their eyesight isn’t perfect, bettas can learn to recognize human faces and respond to their owners over time.
The Role of Iris and Lighting
The iris in a betta fish plays a critical role in managing sunlight, but its limitations highlight the unique challenges these species face. Unlike mammalian eyes with adaptive binocular sight, the retina of a betta fish is less capable of adjusting to fluctuations in bright light or changes in pigment. This limited retinal performance can cause the fish to become startled when exposed to sudden shifts in lighting in their environment.
As a result, improper use of light sources or strong lighting can increase stress and even create potential danger for this freshwater fish. To minimize harm, it’s essential to use soft, even lighting that mimics their natural surroundings.
Despite weak monocular eyesight and poor spatial vision, bettas are skilled at identifying and navigating their aquarium using specialized adaptations. They rely on horizontal streaks, a system of pressure receptors along their body, to detect hydraulic pressure in water.
This system compensates for their non-chromatic perception, allowing them to locate moving objects like bug embryos or other entities in their habitat. Similar to echolocation in dolphins, this capability helps them understand the position of objects, ensuring they thrive despite their visual limitations. The elegant design of these exotic betta highlights nature’s ability to adapt and innovate for survival.
The Betta Iris Functionality in A Day vs Night
Betta fish thrive when exposed to moderate sunlight or artificial light for up to ten hours daily. This light plays a crucial role in supporting their body’s functions, ensuring they stay energetic and healthy throughout the day. Proper lighting provides numerous perks, aiding in their development and helping them maintain a stable activity level. However, keeping them in a dim setting for extended periods can cause health consequences, as their natural need for light is essential for their well-being. In their native environment, they align their basic activities with daylight, using napping and sleeping time to recover and restore their energy.
At night, these species naturally rest in complete darkness, which has been shown to have a positive effect on their health. While some believe minimal sources of light at night are necessary, many researchers argue that such settings could cause harm rather than benefit. Interestingly, bettas lack strong night vision and find it challenging to detect food in the dark, further reinforcing the need for light only during the day. Providing the right setting and proper lights ensures your betta has a balanced and fulfilling day-to-night routine.
How Betta Fish Eyes Work
Betta fish have a unique vision that differs from human eyesight. Unlike our binocular vision, where both eyes work together for a single image, bettas rely on monocular vision, seeing separately with each eye. While they can focus on objects about a foot away, they struggle to align both eyes on one target, making their perception different from creatures with binocular vision.
Betta Eye Shape & Vision
Unlike most terrestrial vertebrates, such as humans, whose irises adjust to focus, a betta fish’s retina remains fixed in shape, preventing it from focusing.
This limitation results in poor depth perception, making bettas heavily reliant on natural light to detect objects and locate prey.
For home aquarists, this means that artificial lighting is essential to help bettas see their food and feed properly. Their monocular vision further affects how they perceive their surroundings, as each eye sees independently rather than creating a single, unified image.
Monocular Vision in Betta Fish
Betta fish, being diurnal, have evolved retinas with more rods than cones, enhancing their ability to detect colored light and perceive color.
Since they are more active during the day than at night, this adaptation makes perfect sense. While their monocular vision limits their ability to see objects and food at a distance, their color perception may be far superior to ours!
The Lateral Lines: A Betta’s Sixth Sense
Like most fish, bettas have developed an extra way to sense and navigate their surroundings—lateral lines. These tiny holes along their body act as pressure sensors, giving them a unique “sixth sense.”
By detecting changes in water pressure, this system helps compensate for their poor iris function and monochrome vision, allowing them to sense movement and objects even in low visibility conditions.
Do Betta Fish Need Darkness While Sleeping?
Betta fish are a unique species that rely on darkness for proper rest, as it helps them release pent-up energy accumulated during the day. While they may occasionally nap in the daytime, they achieve their greatest and most refreshing sleep at night without interruptions. Turning off all lights and surrounding light sources in their aquarium creates a comforting and stress-free environment.
These pet fish spend their days scavenging, searching for nutrition, and wandering in the tank, making it important for them to unwind during the night. Ensuring darkness at night prevents them from becoming anxious or uncomfortable, giving them the possible peace they need to thrive.
Can Betta Fish Eat in The Dark?
Betta fish, being non-nocturnal creatures, struggle with seeing and detecting their food in darkness. Unlike their behavior in the wild, where they hunt for prey during the day, their ability to rely on receptors for locating minute particles is limited in low light. Even though their horizontal streaks help them in detecting nearby items, their overall efficiency diminishes, making it difficult to locate and consume food in such conditions. In captivity, it is best to use aquarium lights during feeding to ensure they can easily find their meal.
At night, these freshwater fish are typically inactive, resting in complete darkness to sleep and conserve energy. While they may seem awake at times, their natural instincts are tuned to avoid feeding in dim environments. Keeping their surroundings free from hazardous situations and providing the right light during feeding times helps create a healthy and stress-free environment for these delicate species.
Also read: How long can your betta go without food?
Which Colors Can Betta Fish Actually See?
Betta fish have a fascinating ability to perceive colors with greater intensity than the human eye, particularly during daylight. Their visual spectrum includes hundreds of hues, allowing them to distinguish infrared colors, green tones, red tones, and blue tones. However, their spatial vision and distant vision are not as sharp as ours.
In the deep sea, their vision depends on wavelength, with higher wavelengths like red traveling and spreading faster but not as deeply as shorter ones. Research suggests that this unique exposure helps bettas adapt to their surroundings, but they may not always perceive certain tones depending on depth.
What Happens if Your Betta’s Eyes Get Too Much Light?
Bettas are naturally more energetic during daylight hours or under artificial light, but overexposure to sunshine, bright lights, or UV rays can make them restless and stressed. This can lead to issues with eating and overall health. Additionally, prolonged exposure to direct sun or extended duration of sunlight increases the water temperature, creating elevated temperatures that can change the water properties. Such conditions can make the water too hot for the fish, potentially causing them to become violent. To keep your betta safe, it is recommended to use artificial lights instead of direct UV exposure and avoid placing the aquarium in the sun for long periods.
FAQs
Are betas colorblind?
Bettas have sharp eyesight for short distances, allowing them to see shapes clearly. They also have strong color vision, making bright hues stand out.
How Many Hours Does Betta Need Light?
Betta fish need at least 8 to 10 hours of light daily. Avoid exceeding 12 hours, as too much light can disturb their natural routine.
Do Bettas Tolerate Led Lights?
Bettas can tolerate LED lights if their daily light cycle is maintained. However, the lighting should not be too intense, as their weak iris function makes it hard to adjust.
Conclusion
Betta fish can see in the dark, but their vision is limited due to slow iris function and monochrome sight.
Artificial light helps them locate food in an aquarium. Maintaining a proper day-night cycle with controlled lighting is crucial for their health and well-being.
