Do Neon Tetras Need Light? (Optimal Lighting For Neon Tetras)

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Neon tetras are hardy creatures, but that doesn’t mean they can survive under any conditions. One question I often get is whether they require light in their tank.

Light is vital for neon tetra development and growth. Use LED lighting in your aquarium for 6-8 hours daily to provide an adequate day/night cycle. Avoid direct sunlight, as it can increase tank temperature and encourage algae growth.

In this article, I will discuss the lighting requirements of neon tetras and show you how to pick up the right one for them.

Do Neon Tetras Need Light?

Indeed, light is essential for neon tetras, and for many reasons:

  • Simulating Natural Habitat: Neon tetras originate from the Amazon basin, where they are exposed to regular cycles of light and darkness. Providing light in their tank helps to simulate their natural habitat and keeps them comfortable and healthy.
  • Circadian Rhythm: Just like humans, fish have a circadian rhythm – an internal biological clock that follows a 24-hour cycle. This rhythm is influenced by light and dark periods. Keeping a consistent light/dark schedule helps maintain their sleep-wake cycle, feeding patterns, and breeding behavior.
  • Promoting Plant Growth: If you have live plants in your aquarium, they will need light to photosynthesize and grow. This not only benefits the plants but also the neon tetras, as a well-planted tank can provide shelter and help maintain water quality.
  • Stress Reduction: Sudden changes in light conditions can cause stress in fish, leading to potential health problems. A consistent lighting schedule can help minimize this stress.
  • Feeding: Some fish are more likely to eat during lighted periods. Although neon tetras can adapt to various conditions, providing a lighted period for feeding can help ensure they get the nutrition they need.
  • Breeding: Light can influence breeding behavior in some species of fish. While neon tetras can breed in a variety of conditions, providing a consistent light/dark cycle can help encourage healthy breeding behavior.

Also Read: Neon Tetra Tank Setup

How Much Light Do Neon Tetras Need?

The best way to ensure that neon tetras receive adequate light is to replicate their natural habitat conditions:

  • Lighting Duration: Aim for about 8-10 hours of light per day, which simulates a typical day period. This provides an ample amount of light for your tetras without overexposing them.
  • Darkness Duration: Ensure your tetras have around 14-16 hours of darkness each day to mimic a typical night period and allow them to rest.
  • Intensity: The light shouldn’t be too bright, as neon tetras come from areas with a lot of vegetation and thus are used to somewhat dim light. The light should be bright enough for the fish to navigate, the plants to photosynthesize (if you have live plants), and for you to view the fish clearly.
  • Consistency: Use a timer to maintain a consistent light schedule. Sudden changes in light conditions can stress fish, so it’s better to gradually change from light to dark and vice versa if possible.
  • Type of Light: Ideally, use full-spectrum aquarium lights. These lights cover all the spectrum and are good for viewing the fish, promoting plant growth, and maintaining the overall health of the aquarium inhabitants.

What Type Of Light Do Neon Tetras Need?

1. LED Lights

A full-spectrum light encompasses the entire light spectrum, stretching from near-ultraviolet wavelengths to infrared ones.

It’s the closest approximation to natural sunlight that you can provide in an aquarium setting. 

This type of light brings out the vibrant colors of Neon Tetras and is beneficial for any live plants in the aquarium, as it encourages photosynthesis.

2. Color Temperature

The color temperature of the light is also important. This is measured in Kelvin (K).

For a freshwater tropical aquarium like the one Neon Tetras would inhabit, a color temperature of around 5,000-7,000K is generally recommended.

This range replicates the light conditions of a tropical daylight setting and promotes the well-being of the fish and plant life.

3. Intensity

Neon Tetras, originating from rivers in the Amazon that are heavily shaded by dense rainforest canopy, do not require intensely bright light.

In fact, too much intense light can stress them. They thrive under moderate or slightly subdued lighting conditions.

Also Read: 11 Plants Your Neon Tetras Will Love In Their Tank

Do Neon Tetras Need Light At Night?

Neon Tetras do not require light at night.

In fact, it’s crucial for them to have a period of darkness for about 14-16 hours to mimic their natural environment and maintain their normal sleep and wake cycles.

Continuous light can cause stress and disrupt their natural behavior.

If there’s ambient light in the room where the tank is located, consider providing a cover or turning off room lights during the night to ensure they have a proper dark period.

What Color Light Is Best for Neon Tetras?

The best light for neon tetras is a full-spectrum or multi-spectrum light.

This light mimics natural sunlight and is the most beneficial for these fish, as it helps to bring out their vibrant colors.

The color temperature should ideally be between 5,000 and 7,000 Kelvin.

That replicates the light conditions of a tropical daylight setting. Too bright or intense colored lights could stress the fish, so aim for a more naturalistic lighting setup.

Also Read: Neon Tetra Tank Size

How to Ensure Your Neon Tetras Receive Adequate Light?

Use an aquarium light timer to manage the duration of lighting:

  • Choose a Compatible Timer: Pick a timer that works with your aquarium light system.
  • Set the Timer: Follow the instructions to set the current time, then program the desired “on” and “off” times, typically an 8-10 hour light period for neon tetras.
  • Connect Everything: Plug the timer into the outlet, and then connect the aquarium light to the timer.
  • Test and Adjust: Test it over one light cycle and adjust the settings as necessary. Check it regularly to ensure it’s working correctly.

My personal recommendation is the Hygger Auto On Off LED Aquarium Light (link to Amazon).

Do Neon Tetra Fry Need Light?

Neon Tetra fry do require light, but their needs are slightly different from those of adult Neon Tetras.

  • Light Requirement: Similar to adults, fry need a consistent light and dark cycle. However, the light should be dim and not as intense as that for adults, as fry are more sensitive.
  • Duration: A light cycle of about 10-12 hours per day is often recommended for fry. This can help simulate natural conditions and support their development.
  • Intensity: The intensity should be kept relatively low to prevent stress. Some aquarists use a lower wattage bulb or place a cloth over the tank to dim the light.
  • Darkness: Provide a period of darkness for rest and mimic their natural environment. This can be for about 12-14 hours per day.
  • Live Plants: If possible, incorporate live plants in the aquarium. These not only help control light intensity but also provide cover and infusoria (microscopic organisms) for the fry to eat.
  • Monitor Fry Behavior: Always observe the behavior of the fry. If they appear to be stressed or unhealthy, adjustments to the light conditions may be necessary.

Can Neon Tetras Survive Without Light?

While Neon Tetras can survive without light for short periods, long-term absence of light can have negative effects:

  • Disruption of Circadian Rhythm: Light plays a key role in regulating fish’s sleep-wake cycles. Prolonged absence of light can disrupt this rhythm and cause stress.
  • Feeding Difficulties: Neon Tetras typically feed during the day. Without light, they may have trouble locating food, leading to malnutrition over time.
  • Stress and Health Issues: Sudden and prolonged darkness can stress fish, potentially leading to health issues or a weakened immune system.
  • Impaired Color Display: Neon Tetras need light to display their vibrant colors. Lack of light may dull their appearance.
  • Plant Health: If your aquarium has live plants, these need light for photosynthesis. Lack of light can harm the plants, altering the balance of the aquarium ecosystem.

Remember, Neon Tetras don’t need light 24/7. They require periods of darkness for rest, just as they would experience in their natural habitat.


Let’s quickly summarize the main points I covered earlier:

  • Neon tetras require specific equipment, including lighting, to support their growth and longevity.
  • Light is essential for enhancing the color and development of neon tetras, as they follow a circadian rhythm influenced by light and darkness.
  • Neon tetras need at least 5-6 hours of light daily to mimic their natural habitat conditions and promote growth.
  • LED lights designed for aquariums are recommended to provide appropriate lighting without affecting water temperature.
  • Neon tetras do not require light at night, as they are diurnal and need darkness to rest.