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Will Aquarium Plants Grow Under LED Lights?

will aquarium plants grow under led lights
There is no denying the fact that LED lights are energy-efficient, emit little heat, and last for years. But, are they really capable of providing lighting conditions necessary to grow healthy aquatic plant’s life?

The answer is; Aquatic plants will not only grow but thrive under LED lights. The key here is to place the lights correctly by considering the tank’s depth and surface area. You don’t want your plants to be exposed to too much light, nor too little but the right amount.

Moreover, knowing the lighting requirements of your plants will assist you in making a better decision. The following article is a quick guide to help you get started with LED lights and create a perfect setup for your aquatic plants. We have covered it all for you, from laying out the factors for choosing the right LED light to simplifying the process for optimal results.

How Good Are LED Lights for Aquarium Plants?

What if I say there is nothing special about LED lights. Even a regular fluorescent bulb will promote plant growth as long as it delivers enough PAR (Photosynthetically Active Radiation) light. So what’s the reason everyone is talking about using LED for their aquarium plants?

It is the very characteristics of LEDs; they have a low cost of operation, emit less heat, last longer, and are an excellent source of controlled light. On top of that, LED lights come in different colors allowing you to aesthetically enhance the overall setup as per your preference.

Probably the best thing about LED is the light spectrum that not only encourages plants growth but penetrates as deep as 24 inches in the water. For better results, you can buy an aquarium-grade LED fixture that often comes in a waterproof glass tube. It can be placed underwater, behind the plants, or anywhere you think it suits well.

Now, you know why LEDs are becoming prevalent, not only in the fishkeeping industry but various others.

To get the best out of it, you have to first know the lighting requirements of your aquatic plants. You can’t simply install a random LED in your aquarium and expect wonders. This is not how it works; you must work through the details to achieve great results.

Different aquatic plants, exotic or ordinary ones, have varied lighting requirements (mainly intensity.) To simplify the matter, some plants require more light than others in order to grow at their best. It can be divided into three categories: low light, moderate light, and high light plants.

Aquatic plants that require low light are easy to maintain. They are often regarded as beginner-friendly as they don’t ask for much effort from your side. Examples of low-light aquatic plants are Anubias, Sagittaria, Java Moss, Java Fern.

Moderate light plants are quite the same as the above and don’t need much attention and care. They include Dwarf Sagittaria, Bacopa Monnieri.

Whereas high light plants, as the name implies, require exposure to high light intensity and spectrum. Some of the prominent species belonging to this category include Rotala Wallichii and Macrandra.

NOTE: This article is primarily focused on using LED lights for common growth-oriented aquatic plants. If you are dealing with exotic species, we suggest you apply the information that is quite precise to the plant. Keep in mind not all aquatic plants are equally easy to work with.

How to Choose the Right LED Light for Your Aquarium

will aquarium plants grow under led lights
Following are the essential factors you must consider when buying LED lights for your planted tank. This will ensure the lights you install are actually capable of the intended job – to promote maximum plants growth.

Tank Size

If you are going to buy a LED light, the first thing you have to take into account is the size of your aquarium and plants placement. It is crucial for all the plants to be equally exposed to the light to have well-balanced growth.

Different size of lights are available for different aquarium size, it is not hard to find the right size of LED light for your aquarium online or offline.

I personally use Fluval Plant 3.0 LED Planted Aquarium Lighting for my 50 gallon fish tank.


As we know, the role of aquarium lights is to mimic the sunlight. The spectrum emitted by sunlight is around 5800K. So with artificial lights, we aim to come as close as to it and within the range of 1200K.

If you have ever bought aquarium grade lights, then you might have come across figures like “5000k“, “6500k“, etc. The good news is you don’t have to worry about these numbers as all plants require the full spectrum of light for proper growth. So regardless of the plant’s species you have in your tank, you can simply go for an aquarium LED light fixture with a “full-spectrum.”

To your knowledge, the full spectrum of light is the different kinds of colors that plants use for the photosynthesis process.

What Color LED Light Is Best For Aquarium Plants?

will aquarium plants grow under led lights
Aquatic plants use all colors of the spectrum for photosynthesis. However, red and blue lights are most effective for plant growth. They help stimulate coloration and higher pigmentation in plants, resulting in better contrast.

When choosing the color for your LED, your aim should be to balance the spectrum while highlighting red and blue light. Besides, to make your aquarium visually impressive, feel free to use any color light.

Tips to Using LED Lights for Maximum Plant Growth

will aquarium plants grow under led lights
There is a common misconception among hobbyists that more light means better results. However, that is far from the truth. If you expose your aquarium with more light than needed, you are going to have algae growing over all your tank.

To ensure your plants get the right amount of light, you have to find the optimal lighting intensity/duration. It’s the key elements that will largely dictate the results you obtain. This is more of a trial and error process where you have to try different variables to find the best settings suitable for your aquatic plant’s growth.

#Tips 1:

If you are experiencing algae growth at a rapid speed, it is suggested to lower down the intensity or duration of the light. You might have to tweak both to determine what gives the best results.

#Tips 2:

There is a famous 4-4-4 rule which you apply for your planted aquarium. It is 4 hours of light, 4 hours off, then again 4 hours of light exposure. Following this process helps build CO2 in the water column, so plants get the required amount throughout the day.

You can repeat this method for a week and observe how it performs in your case. However, there is no hard and fast rule to it; you can reduce the number of hours for lighting exposure when algae start becoming a nuisance.

If you find it a hassle to keep track of the time, you can buy a timer. It will make things easy and convenient for you.

Sings Of Too Much Light On Aquarium Plants

will aquarium plants grow under led lights
Plants have a limit as to how much light they need to grow. When aquatic plants are exposed to an excess amount of light, they will start showing various signs. The most obvious one is fast-growing algae.

If the tips of the plants or leaves have started turning red, brown, or yellow, it means you need to reduce the light duration. Moreover, the plants will grow faster if there is too much light in the aquarium.

There are many other signs to tell this; however, the ones mentioned above are the prominent ones.


As we are on the verge of wrapping up this brief guide on the LED light and its effect on aquatic plants’ growth, we hope you find the read worthy of your time.