Aquarium lights cause algae if their intensity is too high or if they are kept on for long during the day. Powerful electric lights help the algae to thrive. Similarly, white spectrum lights also cause more algae growth. Moreover, blue lights are conducive to algae overgrowth than red lights.
There are a lot of other factors too that contribute to algae bloom in the aquariums. However, since lighting is one of the significant factors for algae bloom, let’s understand its effect in detail.
What Color Lighting Causes Algae?
Algae are autotrophs. It means they photosynthesize their food from light.
Therefore, the more the algae are exposed to light, the faster they grow.
However, some color of lighting plays a crucial role in the rapid growth of algae in an aquarium.
For example, blue lighting causes excess algae in freshwater aquariums.
Whereas low lighting Kelvin, peaking the red, encourages algae overgrowth in marine aquariums.
Also, algae overgrow if they are exposed to white lights extensively.
As per this study, algae overgrow in blue light than in red light.
It’s because blue light occurs at a higher frequency than red light on the visible light spectrum.
How Long Should Aquarium Lights Be Kept On To Prevent Algae?
Different types of algae thrive in different lighting conditions.
For example, some algae thrive in low lighting, while many other algae types thrive in over-lit aquariums.
So you need to first assess the algae type and the reason for their overgrowth.
You can then increase or decrease the lighting of the aquarium.
Keeping the aquarium lights on for more than 10 to 12 hours daily results in algae overgrowth, irrespective of the lighting type used.
So it’s crucial to control the lighting timing, also called a photoperiod, to control algae proliferation in an aquarium.
If the algae bloom is due to excess lighting, you can reduce the aquarium lighting to control algae.
You can keep the aquarium lights on for around 6 to 8 hours per day.
The algae that need intense lighting will shrink back with a shorter photoperiod.
Another way to avoid over-lighting in aquariums is by using the standard output or “NO” fluorescent light bulbs.
You can use light bulbs that emit less than 1.5 watts of power per gallon.
This is particularly helpful if you have a non-planted tank because in that case lighting is needed only to view the tank inhabitants.
Conversely, the algae that multiply in low lighting conditions can be controlled by increasing the lighting duration to around 8 to 12 hours per day.
Excessive lighting will discourage algae growth.
It can sometimes be challenging to keep a close eye on the timing of the aquarium lighting.
So the use of an electronic timer can be helpful. You can set the timer as per your requirement to control the photoperiod.
Do LED Aquarium Lights Cause Algae?
LED aquarium lights cause algae if they are kept on for extended hours and have high intensity. However, LED lights don’t cause more algae growth than other lighting options such as fluorescent lights or metal halide lights.
The advantage of installing LED in an aquarium is that you can adjust the light intensity as per your requirement.
So if you notice algae overgrowth in the aquarium, you can always lower the intensity and the number of hours the light is kept on during the day to control the algae.
For example, if you opt for a 30 watts LED light, the chances of algae overgrowth will be less than from a fluorescent light.
This is because fluorescent lights don’t provide the option of increasing or lowering the intensity.
Many aquarists believe that LED lights deter algae growth in aquariums as most LED lights have a lower intensity than other lighting options, such as metal halide bulbs.
However, LED bulbs can have the same light intensity as fluorescent tubes.
So when it comes to algae bloom, it all depends on the intensity of light and the duration of time the light is kept on, rather than the type of aquarium light.
Moreover, a white spectrum LED light causes more algae growth than a blue LED.
Since LED lights are available in various colors and varying intensities, you should choose the one that best suits your aquarium needs.
Does Blue Aquarium Light Cause Algae?
Blue aquarium light encourages the growth of all types of plants, including algae.
Moreover, blue light causes excess algae overgrowth in freshwater aquariums.
The vital thing to remember is that the intensity of blue light and the number of hours the blue light is kept on will determine whether you will face algae overgrowth in your aquarium.
If the blue light has a moonlight effect, it will not cause algae to bloom if kept on for a few hours daily.
Also, it’s vital to keep a check on the lighting performance. Often tubes and bulbs degrade over time.
If they are not replaced on time, it lowers their Kelvin rating. This results in algae overgrowth in aquariums.