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. Learn how they got their bright fluorescent glow and how you can care for them to live a long, healthy life.
What is GloFish?
GloFish is not one species of fish, but a collection of freshwater fish that have been genetically modified using fluorescent protein genes that are naturally found in corals, jellyfish, and sea anemones. 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.
Currently, GloFish are available in the following options, but more varieties and colors are being developed on a regular basis.
– 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 blue lighting.
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? Their brilliant coloration is not due to injection with dye. It is a hereditary trait passed 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. Betta fish tend to have a short lifespan closer to 2-3 years, whereas some hobbyists have reported owning rainbow sharks up to 13 years.
How much do GloFish cost? GloFish tend to cost more than their normal-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.
A smaller fish tank with no plants will require lots of water changes and filter maintenance to make sure your fish are not living in water polluted by their own 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 larger fish tank filled with lots of plants will help keep the water cleaner and your fish healthier overall.
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.
Do you need a heater for GloFish? All GloFish except for the danios need a heater because they are tropical fish that require temperatures of approximately 75-80degF (24-27degC) to stay healthy. 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? Barbs, tetras and Danios are all schooling fish. You should have at least six species of each species to give them a better experience and decrease aggression. It is okay to have different colors. You could for instance get one tetra each of the following colors to form a six-member school. 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. The semi-aggressive Betta fish won’t get along with other GloFish species, so we recommend only getting one for a 5-gallon tank. See our recommendations for tank mates that you could keep with betta fish.
What does GloFish eat?
Glofish are easy to keep and love variety. The only problem with betta fish is that they prefer to eat below the water surface. You can feed them floating betta pellets and freeze-dried 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.
Are GloFish Hard 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. Try to choose GloFish that are swimming well, have slightly rounded bellies, don’t exhibit any symptoms (e.g., ripped fins or white spots), and are not otherwise behaving oddly. 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.