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Caresheet: Zebra Danio | Danio rerio

Last Updated March 9, 2020
Zebra Danio Caresheet

The zebra danio fish is a spirited and entertaining freshwater species that are inexpensive and great for any beginner aquarium hobbyist. Reaching a maximum size of 2 inches, this hardy fish brings excitement to small setups.

Keep reading for everything you need to know about zebra danio care and keeping them in your own aquarium.

This care sheet is a guest post by Jacques from DragonSearch.com!

Minimum tank size20 gal/75 L (long)
TemperamentPeaceful
DietOmnivore
Temperature65-75 °F/18-24 °C
pH6.5-8
dH5-25 °

Name

Danio rerio is commonly known as the zebra danio or the zebrafish. However, their scientific name is being reconsidered at a molecular level and could soon join the Brachydanio genus, leading to reclassification as Brachydanio rerio.

Natural Habitat

In the wild, zebra danios are found in many bodies of freshwater across South Asia. More specifically, their range includes Pakistan, Bangladesh, Nepal, and Bhutan, with heavy concentrations in the Ganges and Brahmaputra River basins. Their origin has been traced back to the Kosi River basin, which can be found around the lower regions of the Ganges.

However, some zebra danio populations have begun to appear as far east as California, Connecticut, Florida, and New Mexico due to leakage from breeding facilities and pet owners releasing them directly into the wild. They prefer areas with some submerged plants as well as overhead vegetation. The substrate is usually soft–usually sandy or muddy–but sometimes has small pebbles or gravel intermixed.

Technically a cold-water fish (preferring a temperature range of 68°F-72°F), zebra danios thrive in any stream, pond, or river that has a stagnant to moderately flowing current. Zebra danios that have been bred for tropical aquarium use have been heavily inbred and have become less tolerant of colder temperatures.

While zebra danios can survive for more than 5 years in the aquarium setting, they are mostly an annual occurrence in the wild. In a freshwater tank, zebra danios are curious fish who love to race around and explore caves, cubby holes, and the ins and outs of clusters of aquarium plants. The school as a single species as well as with other schools of similar fish in the aquarium. They’re a great, hardy fish to get if you love watching your fish being active and interesting.

This is a highly social schooling species of fish, so it’s best to create a school of at least 6; they tend to adopt a more aggressive behavior in a smaller group.

Identification

Zebra danios are a smaller freshwater fish species, reaching a maximum size of about 2 inches (5cm) in the aquarium setting. They are easily identifiable with 5 horizontal blue stripes along the sides of their signature silver/grey bodies. If you look carefully near their mouths, you’ll be able to spot two tiny whiskers.

Male zebra danios are torpedo-shaped and have distinguished lines of gold between their blue stripes. Females of the same species do not have any gold. Instead, they have plumper bodies, white bellies, and silver stripes.

One common variant, Danio frankei (also known as the leopard danio) is usually considered a variant of Danio rerio and not actually a true species of its own. When purchasing zebras, you’ll often find a leopard danio or two mixed in, or something halfway in between. Regardless, they are both easy tropical schooling fish and compatible with each other.

Other varieties include the rarer albino variety, as well as the long-finned veiltail variants with their long, beautiful flowing tails. However, these fins are susceptible to nipping, so make sure your tankmates will get along with your new fish! Especially popular are the genetically modified, trademarked variety known as the Glofish™; their genes have been altered to glow brightly under black lights and come in many vivid colors.

Zebra danio requirements

Zebra danios are very hardy and resilient, which combined with their low cost in stores, makes them an excellent easy starter freshwater fish. They love well-planted aquariums but also need large, open swimming areas. They live in the middle and upper water column, so it is important to give plenty of space for them to skim along just below the surface. While you usually won’t see your zebra danio at the bottom of your tank, a sandy or silt substrate will make your mini habitat look even more natural!

These fish love moving water and are not too demanding when it comes to water quality, though the aquarium should always be cycled with stable parameters and a good filter. Their energetic behavior does better if you calm them with diffused lighting. Be sure to keep a good lid on the aquarium, as they can be jumpers!

A healthy, genetically-strong zebra danio will live 2 to 3 years on average, and up to 5 years with exceptional care.

Zebra Danio Care Guide

How many zebra danios should be kept together?

At the minimum, zebra danios should be kept in at least a 10 gallon tank. They are schooling fish and need to be kept in groups of at least 6 to meet social requirements. It is recommended to keep 1 fish per every 2 gallons of water depending on size. As mentioned before, these small fish love to swim so make sure you have plenty of room to give them in your tank!

Zebra danio tankmates

If you have slow-moving or docile fish, the fast-moving, robust zebra danio may stress them out. Avoid mixing these temperments with fantail guppies, Siamese fighting fish, and similar slower-moving fish that may be prone to nipping.

Zebra danios, when bought from a breeder, are coldwater fish and prefer moving water. These fish pair exceptionally well with white cloud mountain minnows, which are also a very hardy species that like colder, faster-flowing water. If purchasing your fish from your local fish store, you can fill your tank with other danios, tetras, cory catfish, and smaller loaches. You should have no problems with adding snails to your tank, but shrimp may become part of your zebra’s diet!

As long as you keep your zebra danio with a school of community fish that doesn’t have fins that are easy to nip at, your tank will be filled with excitement and motion!

Zebra danio diet

In the wild, zebra danios are omnivores. This means they will basically eat anything that floats by them in the water, and with a voracious appetite! You should offer your fish a variety of both dry and live foods. If you do not have access to live foods, your local fish store may offer alternative frozen foods. These frozen foods should be dethawed in a separate cup outside of the display tank. A high-quality diet consists of:

  • Vegetables: zucchini, cucumber, peas, spinach
  • Live foods: brine shrimp, bloodworms, mosquito larvae
  • Fish flakes or pellets

It is important to keep in mind that your zebra danios will quickly eat any food you put at the surface of your tank. This means that any fish below will hardly receive any food at all. Make sure that the other fish in your tank are getting the care they also need!

Breeding zebra danios

One little-known fact about this species is that zebra danios mate for life – even if the other mate dies, they do not look for another. If you find you have a breeding pair, try to learn which two are the match, so they can be paired with each other if you decide to isolate them in another tank for breeding purposes.

Start by preparing a 20-30 gallon breeding tank with fine-leaved plants with either a bare bottom or large rocks/marbles. Remember to always put a mesh cover over the top of your fish tank! A breeding tank will also require placing a mesh cover right on top of the substrate; as you’ll see, this will allow the eggs to fall through but prevent the parents from eating them. You can also preemptively treat for any fungi that may have entered the system with a fungicide. Make sure to read the instructions thoroughly as both undertreatment and overtreatment could make you lose the eggs.

Increase the water temperature to 78°F, then place both the male and female in the aquarium. When ready, the female will lay 200-800 eggs, letting them fall through the mesh bottom as the male fertilizes them. Once the breeding and spawning are complete, separate the parents immediately as it is common for them to eat the fry (newly hatched fish).

The fry will hatch within 2-3 days and can be fed up to seven times a day with Infusoria or commercial fry food. If you have access to live food, such as Daphnia or newly hatched brine shrimp, these options are ideal for proper nourishment. The fish will take several months to grow, and should be transferred to larger aquariums as they outgrow their current environment.

Buying Zebra Danios

Zebra danios are easy to find in any pet store, small and large. Premium breeders are common online, and can quickly and safely send you zebras or other fish by mail. Typically this results in no casualties at all if you’re willing to pay high shipping costs to get a better quality of fish.

You can buy zebra danios here!

If you have any questions at all about zebra danio care or behavior, we’d be more than happy to help you out! Leave your questions in the comments below, and we’ll be sure to check in often to share our advice and help you enjoy the hobby to its fullest.

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2 Comments

  • Reply Stephanie January 23, 2017 at 11:39 pm

    Very informative! While I’ve never had zebra danios, just neon tetras and orange mollys, an article like this would have been a big help.

    • Reply Mari January 26, 2017 at 2:41 pm

      Glad you enjoyed it!

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