Care Guide for GloFish – Fluorescent Fish For Beginners

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Care Guide for GloFish – Fluorescent Fish for Beginners

You may have seen brightly-colored fish in a pet shop and wondered what they were. GloFish(r) are an extremely popular fish among beginners because of their stunning rainbow colors, energetic behavior, and resilient ability to live in a wide range of water conditions. How did they get their fluorescent glow? And how to care for them so that they live a long healthy life.

What is GloFish?

GloFish are not just one type of fish but rather a collection of freshwater species that have been genetically modified with fluorescent protein genes that naturally occur in jellyfish, sea anemones, corals, and other marine life. They were originally developed by scientists to study genetics and help detect certain pollutants in the water, but their dazzling appearance made them a popular addition to the aquarium fish industry. The GloFish glows under blue light thanks to their fluorescent genes. This does not seem to affect their quality of living.

GloFish are currently available in the following options. But, new colors and varieties are constantly being developed.

– Zebra danios (Danio rerio) – Black skirt tetras (Gymnocorymbus ternetzi) – Tiger barbs (Puntius tetrazona) – Rainbow shark (Epalzeorhynchos frenatum) – Betta fish (Betta splendens)

Each species has a different husbandry, but we will attempt to give a general overview of their care needs.

GloFish Tetras are genetically modified black skirt Tetras that glow under bright blue light.

What color GloFish are you looking for? At the moment, they come with Moonrise Pink, Starfire Red Sunburst Orange Electric Green, Cosmic Blue and Galactic Purple.

GloFish are dyed? Because they are not injected with dye, their brilliant coloration is a hereditary trait that is passed on from parent to offspring.

Is it illegal to breed GloFish? GloFish are trademarked and patented by GloFish LLC, so only they and their affiliates are legally allowed to breed and sell them. If your fish accidentally reproduce in your home or school aquarium, it is not a problem. Hobbyists and unlicensed entities are prohibited from selling, bartering, or trading GloFish offspring.

What is the lifespan of a GloFish? It depends on the species, but on average, these fish live approximately 3-5 years. While betta fish have a shorter lifespan, they can live for as little as 2 to 3 years. Some hobbyists report rainbow sharks living up to 13 years.

How much do GloFish cost? GloFish tend to cost more than their normal-colored counterparts. The prices range from $6.49 to $24.99 for a GloFish Danio to $24.99 for an elite male GloFish Betta.

How Do You Set Up a GloFish Aquarium?

Most GloFish aquarium kits are quite small, where 10 or 20 gallons seems to the biggest size that is available at mainstream pet stores. However, most GloFish are very active and need to be kept in 20- to 40-gallon aquariums or larger. Also, the blue light that comes with GloFish tanks does not grow aquarium plants very well, which means you may need to add lots of aquarium decorations and fake plants to prevent any aggression among your fish.

GloFish still look very colorful under normal white light and would do well in a beautiful planted aquarium.

For a smaller fish tank, without plants, you will need to do a lot of water changes and maintain your filter. This is to ensure your fish don’t live in water that has been polluted with their waste. (Since the waste chemicals are clear in color, use water test strips to determine how dirty your water is and if it’s time for a tank cleaning.) If possible, buy a bigger aquarium that is not specifically for GloFish. You can use it as long as the aquarium has a “moonlight”, setting that emits blue light, and a white light setting. Then you can add low light aquarium plants that grow under white light during the daytime and naturally consume the toxic nitrogen chemicals produced by your fish’s waste. A large fish tank with many plants will keep your fish’s health better and the water more clean.

Should I turn off my GloFish light? Yes, do not leave the blue light on for 24 hours a day because the fish need to sleep in the dark at night and algae can grow if you turn on the aquarium light more than 12 hours a day. If you find that your fish tank is experiencing green water or excessive algae growth, use a power outlet timer for the aquarium light and number the amount of hours the light is on each day.

GloFish require a heater to keep them warm. Keep them at room temperature between 68-72degF (20-22degC) to avoid them getting sick. A simple aquarium heater will automatically take care of the temperature for you.

How many GloFish should be kept together? You should keep at least six GloFish together. Tetras, barbs, and danios are schooling fish. This will make them more comfortable and reduce aggression. You can get different colors, so for example, you could get one tetra from each color to make a school of six. Tiger barbs can attack other GloFish types, making them semi-aggressive fish. We recommend keeping them in a species-only aquarium that only contains tiger barbs.

GloFish danios are a fast-swimming schooling fish that get along with other peaceful, community fish.

Rainbow sharks grow up to 6 inches (15 cm) long and can be a bit territorial, so we only recommend getting one for a 29-gallon or larger aquarium. Betta fish are also semi-aggressive and won’t do well with the other types of GloFish, so we recommend just getting one for a 5-gallon fish tank or bigger. If you are looking for tank mates to potentially keep with betta fish, see our recommendations here.


What do GloFish Eat?

Fortunately, Glofish are very easy to feed and would love it if you provided them a diverse variety of nutritious foods to eat, such as flakes, pellets, frozen foods, and gel food. Betta fish might be the only caveat because they do prefer to eat from the water surface, so try feeding them floating betta pellets, freeze-dried foods, and frozen foods.

Feed different kinds of fish foods each week to ensure that your GloFish get all the essential nutrients they need for optimal health and coloration.

GloFish are difficult to keep alive

The developers of GloFish deliberately chose the hardiest, most beginner-friendly species possible to make GloFish, so in general, they are fairly bulletproof as long as you keep their aquarium clean and feed them well. However, newly purchased GloFish are sometimes underweight and stressed out, which makes them more susceptible to illnesses. GloFish should be able to swim well, have rounded bellies and not exhibit unusual behavior. We recommend quarantining all new fish that you bring into your home to prevent the potential spread of disease to your aquariums and to treat them more easily with medication if needed. Also, make sure to keep them in larger aquariums of at least 5 gallons for a betta fish, 20 gallons for tetras and danios, 30 gallons for tiger barbs, and 30-40 gallons for a rainbow shark.

We wish you the best with your new GloFish. Our Aquarium Co-Op retail store does not sell GloFish because we believe there is already a huge variety of colorful fish in nature to choose from. To order aquarium fish online, check out our recommended fish sellers below.