Do Betta Fish Like Color-Changing Lights?

Color-changing lights surely bring your Betta-tank’s beauty to everyone’s attention. It’s a good way to grab visitor’s attention. But not at the cost of hurting your Betta fish, right? It’s your duty to make sure such lighting won’t cause any harm to the little fish at all.

Betta fish do not necessarily like color-changing lights. It doesn’t mean such lighting would hurt them. Bett fish usually don’t see warmer tones like red, orange, or yellow that clearly. So, they won’t pick up the change in color anyway.

There’s always a new fad to make your betta tank more aesthetic. It can be a UV-light setting or just a simple color-changing light. But before committing to any of these trends, take a little time to discover every possible side effect on your Betta fish.

Key Takeaways

  • Betta fish don’t really care much about color-changing lights.
  • They don’t pick up the change in color instantly.
  • It is preferable to use dimmed or less harsh lighting (in any color).
  • Color-changing lights don’t have any adverse health effects on a Betta.

Can A Betta Fish See Colored Light?

Betta fish have limited eyesight compared to humans. Still, they can detect up to 300 different shades. The key to understanding how their vision works lies within the structure of the retina. Unlike humans, Bettas have fewer rods and more cones. It changes everything. Rods are responsible for dissecting colors with short wavelengths (like blue or violet). Having more rods in number, we can easily say that bettas see cooler shades better than us.

But they lack sufficient cones in their retina. Hence, it is difficult for them to figure out colors with longer wavelengths. Colors like red, orange, or yellow fall into this category. Such colors already have less frequency (longer wavelength). Once the light hits the water, it loses more frequencies, turning the wavelengths larger & weaker than before.

 So, by the time red or yellow light actually hits the betta’s retina, the wavelength is way past the visible spectrum. That’s why, when you use color-changing lights, most of the warmer tones are practically not noticed by the fish at all. Here is a table to make everything clear.

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Light Spectrum (in nm)ColorVisibility
380 to 450violetVisible
450 to 500blue visible
500 to 565greenvague
565 to 590yellowvague
590 to 625orangenot distinguishable
625 to 750rednot distinguishable

 As you can see, none of the colors except violet and blue are clearly visible to Betta. So, you can use color-changing lights in the aquarium without worrying. It won’t affect the betta at all. They might pick up whether the objects look darker or lighter than usual. But that’s about it. There will be no further reactions or side effects.

Not just blue or violet, though; Bett fish can see wavelength below the human’s visibility range. Their visible range starts from 10nm. Any wavelength below 380 nm falls into the ultra-violet category. The shorter the wavelength, the clearer Bettas see. It’s because short wavelengths are not easy to manipulate by the water. So, there’s not much change in the color’s sharpness or wavelength once it hits the Betta’s retina.

However, UV light is not something commonly used in color-changing aquarium lighting. If you are interested, you would have to get a set of black lights separately.

Do Betta Fish Care About Color-Changing Lights?

Bettas don’t really care about color-changing lights. That must be clear to you by now. However, what they really care about is the brightness level. Bettas don’t prefer harsh lighting, be it in any color. According to experts, each liter of water (in the tank) should have at least 20-25 lumens (unit of light). That’s the minimum requirement to make a particular tank bright and clear for the fish.

If your tank is larger than the average size, you would need more lumens or more watts in an LED light. We have calculated the brightness required for some common tank sizes. Have a look.

Tank SizeRequired Brightness (in Lumens)LED (watt)
5 gallon4505-watt
10 gallon92012-watt
20 gallon185015-watt
25 gallon250027-watt
40 gallon400032-watt
50 gallon450050-watt

 This table is all you need if the tank only has Bettas. You would need more brightness if you have a community tank with various plants. 25 lumens per liter might sound like a lot. But trust us. The light gets dimmed significantly once it hits the water. So, the bettas don’t find it as harsh as you.

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Are Color-Changing Lights Good For Night Time?

Color-changing lights are not a bad idea. It can be used to make your Betta tank appear unique. Also, different colored lights make the aquarium stand out even better. So, why not? But be careful during the nighttime. Bettas don’t like bright lighting when they are trying to get some rest.

Betta fish is pretty easy to keep. As long as you ensure the right water condition and a healthy circadian rhythm, the fish won’t bother you at all. To maintain the rhythm, the tank needs to be dark as much as it’s illuminated. It doesn’t matter what color the LED or incandescent lights are. When it’s nighttime, please reduce the brightness. Usually, in the wild, there’s no source of lighting underwater.

Bettas abstain from hunting and swimming during that time, let the nerves relax. To give the same effect to your pet betta, you need to reduce the brightness of the tank light as well. It doesn’t matter even if you have the perfect colored lights to influence your betta’s health. You must dim it from time to time.

Talking about color-changing lights, the warmer tones are perfectly fine for nighttime routine. Since, these colors are less visible to a Betta, changing colors shouldn’t disturb their sleep cycle. Dimming the lights will make it near impossible for bettas to detect any change in color.

But be-aware of using violet, cyan or blue. We already know, these colors have no contribution to “relax” a fish. Instead, the fish will be seen moving back and forth trying to as a respond to the stimulation. Also, colors like that are clearer to a betta’s eye. So, the fish will notice any changes. We are afraid this might affect their sleep. Try to avoid colors with wavelengths shorter than 400 nm.

How Do I Know If My Betta Hates The Color Changing Lights?

We have already said what matters most to your betta. Even if it’s colored light, you must tone down the brightness slightly. Otherwise, it can hurt the betta. These poor fish can’t sleep peacefully under bright light. A wild betta hardly gets any light after dawn. They like it that way. Light means daytime and vice versa.

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Instead of putting too much consideration into the color, maintain the lighting cycle rigidly. Here are some ways to tell whether your Betta is irritated by the brightness or not.

1. Frenetic Movement

This usually happens when you are using blue or violet lights. These colors have the ability to overstimulate a betta’s eyes and mind. It triggers hyperactivity. You will see the betta swimming aimlessly from one part to another in a weird way. We call it a “frenetic” behavior. It’s pretty easy to identify if your betta is always calm and peace-loving.

2. Increased Stress

Stress level rises because the betta doesn’t get to sleep much. Bright light is the main culprit here, without any doubt. A dimmed or subdued lighting is the key to promoting sound sleep in a Betta. When the light is constantly on their face, they don’t enjoy a long sleeping hour. The lack of rest increases their stress level and tiredness the next day.

3. Lack Of Hunger

One useful tip is to see whether the fish eats as before or not. According to reports, betta fish show a lack of appetite when exposed to excessive brightness. The reason is the same: increased stress. The body assumes it is in danger and doesn’t allow the fish to eat anything. This lack of appetite can last longer than you expected.

Betta fish usually gulps down most of the food within 5 minutes. If your Betta doesn’t show that much enthusiasm anymore, know that something’s wrong.

4. Likes To Hide Behind Plants

What would the betta do to avoid a glaring light? Common sense says they would hide behind objects within the tank. And that’s exactly what they do. If plants are inside the aquarium, the fish would spend most of the time behind them. bettas are not extremely social. They love their privacy, and a “too bright” light stands between this goal.

Before You Leave!!

Even though bettas are fine with any colored lights, there are colors or should we say, wavelengths that trigger certain behavior. For example, blue light is termed a “stimulator.” If the betta is exposed to blue light, it will be more active than usual. Interesting, isn’t it? To learn more about the color theory , check out our article on “which color light does a Betta like”.

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Muntaseer Rahman

About Author

Hello, I’m Muntaseer Rahman, the owner of I’m passionate about aquarium pets like shrimps, snails, crabs, and crayfish. I’ve created this website to share my expertise and help you provide better care for these amazing pets.


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