Many fish owners know that blue light can benefit fish, as it helps them transition from day to night.
But what about shrimp? Can we use blue light with them as well? Is there anything special we need to know first?
Over the years, I’ve learned all about these questions, and now I’m ready to share what I’ve found. Let’s dive right into it.
Can I Use Blue Light In My Shrimp Tank?
People understand the relationship fish have with light. However, they are not as knowledgeable where shrimp are concerned.
If you’re tempted to add a blue light to the shrimp tank, this is what you should know:
1. Can Shrimp Even See Blue Light?
The presence or absence of blue light doesn’t matter if shrimp can’t perceive light, to begin with.
Although, this issue should not worry you, as shrimp can perceive light perfectly, including blue shades.
Justin Marshall (Neuralscientist and fellow of the Australian Academy of Science) performed a study that showed that mantis shrimp perceive their environments via twelve channels of color.
This exceeds the three color channels humans use.
A study (Danielle M. Deleo, Jamie Sickles, Heather D. Bracken-Grissom, Megan L Porter, Tamara M Frank, Tom Iwanicki) published in the Journal of Scientific Reports back in 2020 took things a step further.
Researchers investigated deep-sea shrimp in the Florida Straits. Their results showed that photophores along the shrimp’s body could not only emit light but also detect it.
In other words, Janicella Spinicauda (shrimp) can sense light without using conventional eyes.
This revelation was far from new. A previous study discovered that bobtail squid could detect light using photophores.
Simply put, shrimp are aware of the blue LEDs in their environment, and you are correct in questioning whether the color will benefit or harm them.
2. Does Blue Light Matter To Shrimp?
A shrimp’s ability to perceive light doesn’t mean anything. What you need to know is whether or not that light has a notable impact on a shrimp’s well-being.
Fang Wang, Guoqiang Huang, Shen Ma, Lixin Wu, Xiangli Tian, and Shuanglin (Mariculture Research Lab, Ocean University of China) looked at this matter.
They wanted to know how different light colors affect a Chinese Shrimp’s growth.
They exposed the subjects (Fenneropenaeus Chinensis) to natural, green, yellow, and blue light.
Of these four colors, blue light was the least impactful. The color produced the lowest food conversion efficiency.
However, the researchers admitted that other factors could have influenced the growth rates they observed under different light colors.
Then again, a paper in Comparative Biochemistry and Physiology found that light had no significant effect on a white shrimp’s activity and feeding cycles.
Therefore, you should take a trial-and-error approach. Make adjustments depending on the response you’ve observed in the shrimp.
3. Can Blue Light Improve The Shrimp’s Well-being?
If you don’t even know whether or not light matters to a shrimp, aren’t you better off removing the blue LEDs from the tank?
Do they actually help? Well, yes, they do. Think about it this way. Shrimp don’t exist in a vacuum.
They live in an aquatic environment that includes water, plants, and other creatures. A shrimp’s health is tied directly to the health of the aquatic environment.
In other words, any element that benefits the aquarium is also good for the shrimp. Blue light is a positive addition to an aquarium for various reasons:
- Blue light is suitable for fish. It can calm agitated creatures, reducing their stress. That even includes aggressive species like betta fish.
This is good because agitated fish are more likely to eat their weaker neighbors. And unfortunately, shrimp are weak. They can’t fight back against aggressive fish.
- Blue light creates a seamless transition between day and night time.
This is another factor that prevents stress in fish, and stress-free fish make for appealing neighbors in a shrimp tank.
- Blue light is good for plants, and shrimp will thrive in a tank with healthy plants.
Yes, blue light can boost algae growth, especially if your LEDs are always on. But you can keep algae levels under control without removing the blue lights.
As a side note, it’s worth mentioning that shrimp like to eat algae, so it might even be good for them. Having algae is not always a bad thing.
- Blue LEDs improve a tank’s visual appearance. They can also enhance the shrimp’s colors, making the aquatic environment more attractive.
This matters because most people rear fish and shrimp for the sole purpose of looking at them.
How Do I Properly Use Blue Light In My Shrimp Tank?
Blue lights are only dangerous when you misuse them. You can protect your shrimp’s well-being if you keep the following in mind:
1. Choose A Relatively Shallow Tank
The tank’s dimensions matter. Some people unknowingly encourage algae to grow by installing strong light sources.
They do this because their tanks are too deep. They need stronger light sources to compensate for the depth.
You can tolerate a deep tank if you have the time and resources to combat the consequences of a strong light source, which includes high temperatures.
But it is much easier to acquire a shallow aquarium. The height should be half the tank’s length. This makes softer light sources an option.
2. Prioritize LEDs
If possible, use LEDs. They are cost-effective, energy-efficient, and durable. They also generate less heat.
Many aquarists gravitate towards fluorescent lights because they are cheap and easily accessible.
You can make do with the fluorescent option in the absence of LEDs, so long as you avoid incandescent bulbs.
They generate too much heat because of their inefficiency. Metal halides have a similar problem. Their heat is too intense.
If possible, just stick to LEDs.
You can dim them where necessary to prevent algae explosions. I personally went with the Hygger Full Spectrum Aquarium Light (link to Amazon).
3. Adjust The Intensity
Identifying the correct intensity to promote plant growth without boosting algae growth is not an easy task.
If you want to minimize the light intensity, prioritize low-light demanding plants. They can survive in environments with 75-100 umols.
These are the PAR values. PAR is photosynthetically active radiation. The figures show you the amount of light that is available for photosynthesis.
Here are some examples of low-light demanding plants:
- Java fern
- Java moss
- Amazon sword
- Marimo ball
4. Schedule The Lighting Properly
Maintain a strict schedule. If you’ve decided to add blue LEDs to the tank, turn them on and off at the same time every day.
Most aquarists maintain 8 to 12 hours of daytime and 8 to 12 hours of darkness.
If you only use blue lights during the transition to nighttime, you can turn them on when the sun goes down.
Switch them off before you sleep to maintain the scheduled day/night cycle mentioned above. Ideally, the blue light should be on between 6 pm to 11 pm.
What Color Light Is Best For Shrimp?
Researchers (Biao Guo, Shuanglin Dong, Qinfeng Gao, Fang Wang) looked at the impact of rhythmic light colors on a shrimp’s molting and growth.
They published the results in the Aquaculture Journal. The shrimp that lived under conditions with a blue light during the study recorded the smallest growth.
The highest growth rate was seen in the blue light to green light (fluctuating light color treatments) group. But does this make blue irrelevant?
Another study in the Journal of Crustacean Biology (Ji Yong Choi, Cheol Young Choi, Jong Ryeol Choe, Jeongrack Koh) classified blue light as a stress factor under osmotic conditions.
In contrast, green and red lights reduced stress in Lysmata amboinensis (Ornamental Cleaner Shrimp). The researchers performed this study in a marine environment.
What does this tell you? You can’t predict the impact of blue light on an aquarium. Numerous factors will influence a shrimp’s response to this color.
Therefore, rather than looking for the best color for shrimp, you should take a moment to determine whether or not you really want to add blue LEDs to the aquarium.
Fish and plants will thrive under blue light. You don’t lose anything by adding this color to the tank.
And if you select any other color, you can also make it work. There is no such thing as the best light color for shrimp.
Although, a paper published by Dariano Krummenauer, Wellica Gomes Reis, Wilson Wasielesky, Hellyjunyor Brandao, and Paulo Cesar Abreu showed that Pacific white shrimp grew best under green light.
Blue light is great for a shrimp tank because it is beneficial to their environment. If used correctly, the fish will be calmer and the aquatic plants will flourish.
And if the shrimp’s environment is healthy, they will thrive. Blue lights also help the shrimp themselves transition from day to night.
If you choose to use artificial lights in your shrimp tank, know that you should aim for 8 to 12 hours of darkness, as the creatures need to sleep. This also applies to blue lights.