There are many fish that glow. However, not all fish glow under blue light.
Glofish is the only fish that glows explicitly under blue light.
So, let’s learn more about this unique fish and why it glows under blue light.
Interesting Facts About Glofish
Glofish is a trademarked and patented fish.
These fish are genetically modified with fluorescent proteins that occur naturally in jellyfish, corals, sea anemones, and other marine creatures.
The glofish species comes in five colors: Starfire Red, Electric Green, Sunburst Orange, Cosmic Blue, and Galactic Purple, although not all species are available in all colors.
Scientists initially developed glofish to help detect certain pollutants in the water and for genetic research.
However, they soon become an industry favorite due to their attractive colors.
Most glofish varieties are schooling fish and can be kept in groups of 5 or more, except Glofish Shark and Glofish Betta.
These fish prefer a planted tank with plenty of hiding places in the form of caves, rocks, hollow logs, and other decorations.
Glofish eat various types of food, such as commercial flakes and pellets, and frozen or freeze-dried food.
Foods containing beta carotenes and carotenoids can help improve their colors.
Along with a healthy diet, regular water changes and proper filtration are essential to ensure the good health of a glofish.
What Makes Glofish Glow Under Blue Light?
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Glofish aren’t a natural fish species.
They are genetically modified fish from various species, namely tetras, rainbow sharks, zebrafish, tiger barbs, and, most recently, bettas.
Glofish produce a fluorescent color from an inherited bio-luminescent protein gene.
In 1999, Singapore scientists extracted a gene called the “bioluminescence gene” from jellyfish and injected it into the body of a zebra danio embryo to experiment.
Due to this experiment, a new species with fluorescent protein was created.
Later, they used the same method on various other fish species, thus creating different glofish varieties.
This protein makes a glofish glow under blue light and other dark shades.
Glofish absorb light at a specific wavelength and then emit it again to give off their luminescent glow.
This protein is also found in sea anemones and other marine organisms.
The reproductive process of glofish passes the fluorescent gene from the parent fish to their offspring.
Hence, a newly born glofish also glows under blue light.
How to Make Glofish Glow Under Blue Light?
Glofish don’t glow unless exposed to UV light. Hence, you need a light source that emits ultraviolet light to make them glow.
Firstly, you should set up an aquarium with a dark background and a blue LED light.
This will help the glofish absorb more blue light and emit their fluorescent colors.
After setting up the aquarium, you can install the following lights for the glofish to glow:
- You can buy special LED lights designed explicitly for glofish from pet stores or online stores. These lights are usually blue and emit UV light at a wavelength ideal for making the glofish glow.
- You can also purchase UV-emitting light bulbs for your aquarium. These bulbs release a high amount of UV light, stimulating the glofish to generate more protein genes that make them glow.
- Actinic lighting is another type of lighting that can make glofish glow. This type of lighting emits a blue light ideal for making them glow.
- Another option is adding some decorations in the aquarium that reflect blue light. This will help the glofish absorb more blue light and emit their fluorescent colors.
- You can also enhance the florescent colors of glofish by feeding them a well-balanced diet that will keep them vibrant and healthy. Carotenoid-rich foods are known to increase the coloration and vibrancy of glofish.
- Exposing glofish to sunlight for a few hours each day is also an excellent way to enhance their coloration. Sunlight contains abundant UV rays, which can help the fish produce more glowing protein. Be careful not to leave them in the sun for too long because the water may overheat and prove fatal.