Care Guide for GloFish – Fluorescent Fish for Beginners

You may have seen brightly-colored fish in a pet shop and wondered what they were. The GloFish(r), a very popular fish among beginners, is because of their amazing rainbow colors, energetic behavior and resilience to living in all kinds of water conditions. Find out how they got their fluorescent glow and how to care for them so they live a long and 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. GloFish’s fluorescent genes make them glow brightly under blue light, which does not seem to have any effect on their quality life.

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 colors are GloFish available? They come in Moonrise Pink and Starfire Red, Sunburst Oranges, Electric Greens, Cosmic Blues, and Galactic Purple.

Is GloFish dye-injected? 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. However, the sale, barter, or trade of GloFish offspring by hobbyists and other unlicensed entities is strictly prohibited.

What’s the average lifespan of GloFishes? It all depends on what species you have, but they generally live between 3-5 and 5-7 years. The lifespan of betta fish is usually between 2 and 3 years. However, some hobbyists have been able to keep rainbow sharks for up to 13 year.

How much do GloFish cost? GloFish are more expensive than their regular-colored counterparts. At the time of this article, they range in cost from $6.49 for a GloFish danio to $24.99 for a premium 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.

Smaller fish tanks with no plants will need more water changes and filter maintenance in order to ensure that your fish do not live in water contaminated by 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. If you keep them at a room temperature of 68-72degF (20-22degC), the continuous stress of being too cold can cause them to get sick. A simple aquarium heater will automatically take care of the temperature for you.

How many GloFish can you keep together? Danios, tetras, and barbs are schooling fish, so you should get at least six of the same species to make them feel more comfortable and lessen aggression problems. 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 is a fast-swimming schooling fish which gets along with other peaceful, communal 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. See our recommendations for tank mates that you could keep with betta fish.

What do GloFish Eat?

Glofish are easy to keep and love variety. 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.

Is it hard to keep GloFish 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. GloFish can become stressed and underweight after being purchased, making them more susceptible to illness. Choose GloFish with rounded bellies that swim well and don’t show any signs (e.g., white spots or ripped fins) and who behave normally. 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.