What Color Lights Do Fish Like?

If you’re planning on upgrading your aquarium, or simply want to renovate the one you currently have, changing out the lights might have crossed your mind.

With newer kinds of lights and a number of different colors now available, you can choose from a vast variety.

Of course, one thing that you might be concerned about is whether the lights you opt for are right for your fish.

Different kinds of fish prefer different colors and intensities. Some fish also prefer lights to be on for longer durations while others get uncomfortable if they’re on for more than a few hours.

Apart from a fish’s preference, you might want to choose lights based on how they make your fish appear as well.

Certain lights really bring out the vibrant colors of a fish, while others work against them to make them appear dull or pale.

The most common colors for aquarium lights are blue, red, and white. The most common kinds of lights are LED lights.

Depending on the kinds of live plants you have in the aquarium, you may or may not need more lighting. More than fish, the plants depend on the lighting to stay healthy and grow.

Here’s what you need to know about different aquarium lights.

What Color Lights Should You Get for Your Aquarium?

Here some colors you can consider when getting lights for your aquarium:


Blue lights are great for your aquarium plants. They’re also exceptional for your fish because of the calming effect of blue.

If you have a combination of very active and slower fish, blue lights allow them to rest comfortably and provide enough light for the active fish to keep swimming around.

If you have blue, green, and, red fish, blue light helps accentuate their color. It also brings out the colors of your aquarium plants, especially if you have red ones.

If you keep moonlight blue bulbs, they can be kept on during the night, unlike many other lights that can be too bright and overwhelming for fish to be kept on all the time.


White lights work best for blue-colored fish. They’re also the commonly chosen color of lights and are available for all sorts of lighting options, as we will discuss below.

However, some fish owners will say that white lights don’t work as effectively in keeping your plants healthy.

When you do go for white light options, go for a full spectrum lighting option that has more colors.

This helps ensure that your plants get all the frequencies of red, blue, and green that they need to photosynthesize effectively.


When you have nocturnal fish, a red light might be better in ensuring that they can venture out at night without getting overwhelmed.

They’re a bit dull and warmer, which means bottom-dwelling fish feel more comfortable in coming out of hiding and swimming around despite the light.

If you have fish such as catfish or plecos, they will respond more positively to red lights. They’re also great for plants because they encourage them to reach greater heights and grow more flowers.

It’s important to note that if you do get red lights, you can’t keep them on all the time. That’s because red lights are interlinked with more algae growth.

Algae rely more on red light frequency to grow, so you will have to keep a careful eye on your aquarium’s algae growth with red lights, and keep the lights switched on for a shorter duration.

Also read: Can Aquarium Fish See At Night/Dark?

What Lights Are Best for Your Aquarium?

The four most common kinds of lights for aquariums are normal output fluorescent lights, compact fluorescent lights, high-intensity metal halide lighting, and LED systems.

These vary in their energy consumption, intensity, and options when it comes to color choices.

LED Fixtures

These are one of the newest light options for aquariums. They’re one of the least energy-consuming ones as well. They come in a variety of colors and can be used for multiple species of fish.

Depending on how far away the LED light is fixed, different plants and other aquatic life can benefit and thrive safely.

LED lights can be in many different colors, such as blue and white.

Depending on which kind of lights you get, you can use these blue and white lights to resemble both night and day environments, which means that LED lights can be used throughout the day.

Because they are made to be used for both saltwater and freshwater fish, they come with the option to create numerous underwater environments.

They bring out the color of every fish, so you can clearly see whether a fish has paled in color.

Additionally, if you’ve got a collection of brightly colored fish, LED lights are the most likely to enhance every color and make your aquarium look vibrant.

Normal Output Fluorescent Lighting

If you have fresh and saltwater fish in your aquarium, these lights can be a good choice. They are energy efficient, generally easy to set up, and can be adjusted until you find the right setting for your tank.

You can find normal output fluorescent lighting in the form of actinic white bulbs, which give off blue and white light. These create an environment similar to a fish’s natural habitat.

It’s about 10,000°K. If you’ve got corals, they are exceptional in helping them grow and stay healthy.

Another option is the color-enhancing bulb. These are generally warmer lights, which means that they give off an orangish-yellow hue which makes the aquarium environment appear warmer and more pleasant.

They work well for aquariums with freshwater and saltwater fish, but not for aquariums that have live plants. These bulbs are exceptional in bringing out the colors of your fish to the fullest.

Third in the normal output, fluorescent lighting options are the high-intensity bulb. This gives off a very bright light with a Kelvin temperature between 10,000 to 20,000 degrees K.

This is a sharp white light that works best when you use it with actinic bulbs, which we’ll discuss below.

One advantage of this light is that the white light helps your tank resemble deep-water environments that are cooler, which is preferable for fish that come from deeper waters.

The actinic bulb gives off mainly a bluish light that again resembles deep water environments.

They help with coral growth because of their light energy levels and work best if you have a reef aquarium. Please note that this is different from the actinic white bulbs.

Last, in the normal output, fluorescent lighting options are the full spectrum or daylight bulb. These give off every wavelength for visible light—which means that they are the closest to natural lighting (the sun).

Because they have a combination of colors, they work well with all sorts of fish and for all sorts of aquarium environments.

Metal Halides

These lights are quite common among many aquarium owners. They have a very high light intensity and work best for reef aquariums.

If you have fish and aquarium plants that need higher intensities of light, going for this option might work best for you.

One thing to note about metal halides is that they are usually used in aquariums that are at least 2 or more feet in depth because their intense lighting is capable of traveling through more water.

If you have fish that prefer swimming near the bottom of the tank, this light could work in ensuring they still receive enough lighting.

Compact Fluorescent Lighting

As compared to standard fluorescent lighting, these lights have a higher output of light. They give out more light in one bulb than multiple bulbs combined in other lighting options.

They’re relatively easy to use and have nearly all the same benefits as normal output fluorescent lighting.

You can use this option for freshwater fish. They’re easy to afford, do not give off as much heat, and come in a number of lighting options.

Does Light Intensity Matter?

Light intensity is very important in ensuring that your fish and plant life stay healthy.

Most brightly colored green plants will prefer brighter light, while duller green plants will prefer less vibrant lights, generally.

If you have many aquarium plants, you will need brighter, or heavy lights.

Because your plants generally grow at least two feet below the surface, a higher intensity light is necessary to reach them and ensure effective photosynthesis.

If you only have fish and don’t have to worry about how your aquarium plants will respond to light, then low light is an acceptable option.

Heavy or bright light is around 4 or 5 watts or fluorescent grows light per gallon, while medium light is around 2-4 watts of fluorescent grow light per gallon.

Low lights fall somewhere below 2 watts. Both medium and low lights are viable options for an aquarium with only fish and no live plants.

Final Words

Hopefully, you now have a better idea of what colors and what kinds of light to go for depending on your fish and plant life.

It’s important to be able to clearly see the distinct colors of every fish and plant because it helps you determine whether they are healthy and also creates a vibrant and aesthetic sight no matter where you place your aquarium.

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