How To Choose The Best Grow Light In Aquaponics

How to Choose the Best Aquaponics Grow Light

Many aquaponics growers choose to set up their own system indoors because of the benefits it gives them. These indoor aquaponics systems are often built inside a garage, basement, spare room, and kitchen. Because an indoor aquaponics system does not have access to any direct sunlight, grow lights are necessary. 

Plants need light to grow, and indoor aquaponics growers need to provide artificial lighting to their indoor plants to help facilitate photosynthesis. Many artificial lighting systems are readily available in the market, but choosing the best grow lights for your indoor aquaponics system is essential for plant growth. This blog explains the considerations you need to make when choosing the best grow light.

Why Do Plants Need Light?

Light is one of the essential factors for an indoor aquaponics system. All plants need light for photosynthesis, which converts light, water, and oxygen into carbohydrates (energy). Plants require this energy to grow, bloom, and produce fruits. Without enough light, the carbohydrates will not be manufactured, and the energy reserves will deplete, and plants will die. 

It is essential to provide adequate light to your plants. Different plants need different amounts of light, but as a rule of thumb, vegetables and flowering plants need at least 12 to 16 hours of light per day. Plants also need darkness, so you must also provide them with at least 8 hours of darkness per day.

Grow Light Spectrum

There are several types of grow lights, and each of them has its advantages and disadvantages. To understand the purpose of a grow light, you need to look at its light spectrum. Here’s the detail in the graph below.

Grow Light Spectrum Chart

Graph Explanation:

  • White Light– The middle between 500 to 600 nm. The white light represents the sun, also known as solar light, and is considered the full spectrum.
  • Blue Light– Blue light is essential during the plant’s fruiting stage. 
  • Red Light– The red light is essential in the foliage stage of plants or the growth and grouping of their leaves. 
  • Visible Light– This is what human beings see. The visible light is also known as “PAR” (Photosynthetic Active Radiation) and is an important section of the light spectrum chart because this is what the plants need. 
Grow Light

What Color Of Light Is The Best For Plant Growth?

The color of light is also essential in plant growth. The color of light in plants refers to the color temperature of the light. Of all the colors in white light, the plants mostly use blue and red wavelengths. Blue triggers the plant to make more leaves, while red triggers more flowers and fruits. Use grow lights that aim for the PAR light spectrum because you will be growing different varieties of plants in your indoor aquaponics system. 

Factors To Consider Before Buying Grow Lights

  • Types of Plants

The most important thing you need to consider is the type of plants being grown or planning to grow in your system. Less intense lighting is suitable for plants that do not flower or produce fruits, while intense lighting is suitable for fruits and flower-bearing plants.

  • Light Spectrum

Understanding the different colors of the grow lights spectrum is also essential in choosing the best grow light for your indoor aquaponics system. As explained above, each color has specific effects on plant growth. So know the meaning of each color to choose the right grow lights for your plants. 

  • Strength

The grow light’s intensity is measured through lumens, which is how much brightness the light emits when placed one foot away from the lighting area. When buying grow lights, always read the lighting label to identify its lumens level.

  • Efficiency

In choosing the best grow light for your system, you should also consider the grow light’s energy efficiency to lessen the energy cost. 

  • Cost

Some grow lights are expensive, while some are not. To choose the best grow lights for your indoor aquaponics system, do not only look at the upfront cost of buying a grow light but also it’s quality and maintenance cost.

Grow Light Placement

Hanging or placing your grow lights over the plant beds is the best grow light placement, as it mimics the natural sunlight from overhead and exposes all the sides and leaves of the plants to artificial light. 

When you hang your grow lights, always consider the type of plant you have and how tall it can grow. Keep your grow light close to the plant as much as possible, but not too close that it will burn your plant.

 Here’s our guide on grow light placement in your aquaponics system:

  1. Fluorescent lights can be placed 12 inches over the plants.
  2. HID lights can be hung 12 to 48 inches above the plants, depending on your wattage.
  3. LED light emits less heat so that you can place them 6 inches over plants.

You can also research the type of plants you want to grow and their light requirements to determine how much light they need. One thing you can do to test if the distance between your light and plant is correct is to test by placing your palm down over your plants. If the top of your hand becomes hot, you need to adjust your light’s placement. Too much heat will burn your plant, and your plant will also grow in height, so you need to check and adjust the placement of your grow light as your plant grows.

Lighting Choices For Aquaponics

There are several types of grow lights available, each with its strength and characteristics. However, most aquaponics gardeners are looking for a full daylight spectrum light that is energy-efficient, low cost, and suitable to grow a wide variety of plants. Based on these factors, here is our list of the daylight-spectrum lighting options available for aquaponic gardeners.

 1. Compact Fluorescent (CFL)

Compact fluorescent lights are the newer form of fluorescent lighting and come in many wattages. CFL grow lights are a cheaper lighting option for small aquaponics gardens. This type of light can last longer than ordinary incandescent bulbs. They are low heat and produce a decent spectrum of light for growing plants. CFL should be used only as supplemental lighting to your indoor aquaponics garden when you can get at least some sun each day. In buying CFL, look for bulbs that are labeled as grow light. Here are some advantages of CFL:

  • Energy efficient
  • You can place CFL near the plants because it does not emit too much heat.
  • It is readily available in garden or electrical and even online stores.

2. High-Density Discharge (HID)

High-Density Discharge is another kind of indoor lighting that is brighter and more intense than other lighting types. The HID system is composed of a socket, lamp or light bulb, ballast, and a reflector. The HID light has an awkward shape and is often used in conjunction with a reflector that directs the plants’ light. HID grow lights are more efficient than fluorescent lights and a better choice for more extensive and light-demanding indoor. HID bulbs have a high light output level and are often used by commercial aquaponic growers. Here are some advantages of HID lighting:

  • HID light can be used for a longer time without affecting the temperature.
  • Safe for plants because it emits limited harmful wavelengths that can cause plants to dry or burn.
  • It has no mercury content, so it is environmentally friendly. 

3. Light-Emitting Diodes (LED)

Light-emitting diodes are the best in the market today, but it is expensive compared to the other grow lights. The reason for this is that LED offers a distinct advantage over the other grow light choices. These are:

  • Lack of heat – you can put the light closer to your plants without burning the leaves. 
  • LED grow lights only emit light that is usable to plants.
  • Energy-efficient.
  • Long life. 

In using LED, there is no need to use ballast, reflectors, or running cables in between since all the electronics are within the unit. LED grow lights can be used in tight spaces and operate at a lower temperature, so you can control your grow room temperature quickly.

One disadvantage of LED light is that it is expensive, but if you want to invest in a long-lasting, efficient grow light, LED lights are a great choice.


Grow lights are a necessary component of indoor aquaponics systems. So it would help if you choose the best grow light to get the most out of your system. There are several types of grow lights that you can use, some cheaper and some more expensive. Choosing which light is the best for your system can be quite overwhelming, but if you know the different types of grow lights and what your system needs, you can easily decide which grow light to purchase.