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Do Fish Need Light In Aquaponics Systems?

Do Fish Need Lights In Aquaponics Systems

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As the agriculture industry progresses alongside technology, innovative farming equipment emerges as well. This includes supplementary or artificial lighting, which is widely used today to grow fruits and vegetables in a controlled environment. Scientific studies have proven the effectiveness of using artificial light on plants. However, as more people engage themselves in contemporary methods of farming such as aquaponics, practitioners begin to wonder if using artificial light on fish can also have its own set of benefits. Which begs the questions, do fish need light in aquaponics systems? What are the benefits and drawbacks of exposing aquaponics fish to artificial light?

Light is not necessary for fish to survive in an aquaponics system. However, adding artificial light to your fish tank may improve egg production and health. To date, modern technology has helped create innovative light solutions for fish either for aquaculture or aquaponics. Using the right type of light is crucial to your fish’s health to avoid stress and poor health. Note that the relation between light and fish health is still a controversial topic in the scientific community

In this article, we will discuss how certain types of artificial lighting may help your fish, which species require light, and which ones would thrive without it.  

Why Fish Need Light in Aquaponics System

Why Fish Need Light in Aquaponics System

Generally, fish need light only to see their food. But newer research suggests that it has other benefits for your livestock. According to the study, aquatic animals are naturally sensitive to light. The intensity, spectrum, and photoperiod can contribute to fish productivity, behavior, and overall health. 

Also, specific types of lights are intended to regulate temperature and could be a good alternative for heaters. This is ideal if you live in a colder region yet would like to raise fish that thrive in warmer conditions like tilapia.

Choosing A Light For Your Fish 

Since artificial lights for fish are more complex, we would like to share with you the right features when choosing the best one for your system.

LED Light

We recommend getting an LED light where you can easily adjust its intensity depending on what your fish requires. Plus, this type of light is known to have a long life span and is considerably more cost-efficient.

Incandescent and Fluorescent Light 

Other types of lights can be used as well, including incandescent and fluorescent lights. However, these types have limited features, and adjusting its intensity and heat is not possible. If you plan to use these, do so with extra caution as this could cause abnormal light-induced biological responses such as being too aggressive. The heat issues brought by these types of lights can also affect the health of your fish.

Light Distribution

You may also consider getting an artificial light that has a vast light distribution. This is important, most notably for aquatic creatures. 

Lights could naturally increase the temperature of your water. If the light distribution isn’t equal across your fish tank’s overall area, only a portion will become warmer, and the rest will remain cold. This sudden change of temperature could cause stress on your fish.

Easy Installation and Maintenance

Using supplemental farming equipment such as lights could mean an added task in your aquaponics checklist. Thus, for practicality reasons, target an artificial light that is easy to install and to maintain.


Ideally, you should never leave your light on for 24/7, considering the health issues that your livestock might encounter. Too much light can also promote the growth of algae, and it could consume the nutrients for your crops and fish. Also, your electric consumption might increase if you do not monitor your light’s usage. Getting a timer can help these issues.



Got Lights?

How Much Light Do Aquaponics Fish Need?

As a generic rule of thumb, most fish would benefit from around 12 hours of light per day. This may vary depending on the fish species and the overall environmental conditions of your aquaponics system. To understand how much light your fish need, you need to consider the following: 

  • Natural light conditions   
  • Climate and temperature 
  • Fish species  

These will be explained further in the succeeding sections.

Natural or Artificial Light for Aquaponics Fish

Both natural and artificial light are beneficial for aquaponics fish, and choosing one over the other doesn’t necessarily have to be an absolute decision in all cases.

Natural Light Source  

If you live in a tropical region where there is an abundant natural light source, you can use that to your advantage. However, too much of it can put your fish in great danger. So to balance it out, place your fish tanks in a shaded area or use additional coverings such as tents. By doing so, you are protecting your fish from extreme temperatures and excessive growth of algae.

Artificial Light Source

Artificial light for aquaponics fish is ideal if you have an indoor setup or if your fish species have particular requirements to thrive. This way, you can simulate the natural environment for your fish.



Got Fish?

Do Aquaponics Fish Need Light During the Night?

Fish do not necessarily need light at night time. In fact, they require both periods of day and night. Like humans, they need to sleep, and they will do so better in the dark. 

We also need to consider the effects of using too much light on your fish tank, as stated in the previous sections. If your fish need warmer temperature, using actual heaters at night is a better solution instead. 

Which Aquaponics Fish Need the Most Light?

In this section, we included fish that need at least eight hours of light every day.  

First is tilapia, as this is probably the most popular aquaponics fish that practitioners use. It requires at least 18 hours of light per day. So, apart from natural light, you can augment it with an artificial source. Another aquatic creature that thrives well with an ample supply of light is yellow perch with a requirement of 16 hours per day.  

On the other hand, ornamental fish species such as goldfish and koi need 12 to 13 hours. This is beneficial to maintain the sharp colors of their scales. It may also improve their immunity to fight off common fish diseases. Other types of fish, such as mollies and guppies, need at least eight to 12 hours of light.

Fish Type Light Requirement (in Hours) 
Tilapia  18 Hours 
Perch  16 Hours 
Koi  12 to 13 Hours 
Goldfish  12 to 13 Hours 
Mollies  12 Hours
Guppies 12 Hours 


Which Aquaponics Fish Need the Least Light?

There are fish types that cannot tolerate bright lights, and it would be best to use a minimum amount of light or not to use one at all. Examples are bass and walleye.

Salmon and trout eggs couldn’t survive excessive light as well. So if you are raising these types of fish, using artificial light for several hours could affect production and must be avoided.

Conclusion: Do Fish Need Light In Aquaponics Systems?

The answer is both yes and no. It largely depends on the fish species, temperature, location, and the overall condition of your aquaponics system. Thus, before getting an artificial light for your fish, you may refer to our recommendations above to make an educated decision. 

Lastly, include regular monitoring of your light because the intensity can change over time. As this happens, it will have a lesser effect on your fish, and replacing it might be necessary. 

The Campbells love finding sustainable and fun ways to increase their independence from traditional brick and motor supermarkets. Aquaponics provides a full lifecycle food source for families and a great hobby. #aquaponicslifestyle

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