If you want a high-energy, colorful fish in your freshwater tank, grab a giant danio. The schooling fish will keep you mesmerized while swimming in laps.
It is also easy to care for and raise, making them the perfect choice for beginner aquarists. You only need to have a large enough tank with the suitable tank mates and water conditions.
Intrigued to know more? Let’s dive into the fascinating world of these species.
Species Overview
| Origin | Asia: India, Myanmar, Nepal, Thailand, Sri Lanka, Indochina, River Ganges and Mekong: Mekong basins |
| Order | Cypriniformes |
| Family | Cyprinidae |
| Scientific Name | Devario aequipinnatus |
| Common Names | Giant danio, Sind danio, Malabar danio |
| IUCN Red List Status | Least Concern |
| Appearance | Long and sleek torpedo-like body, iridescent gold body, electric blue spots, and stripes, light yellow and transparent fins, rounded fins with a forked tail |
| Size | Up to 15 cm (5.9 in), 12 cm (4.7 in) on an average |
| Lifespan | 5-7 years |
| Temperament | Slightly aggressive, non-territorial |
| Tank Level | Mid and upper-level |
| Water Temperature | 72-75 °F (22-24 °C) |
| pH Level | 6-8 |
| Water Hardness | 5-19 dGh |
| Care Level | Moderate |
| Minimum Tank Size | 55 gallons for a school of 5 fish. Must be more than 36 inches in length. |
| Tank Environment | Heavily planted tanks with driftwood and caves for resting and hiding. |
| Diet | Carnivorous, omnivorous and planctophage |
| Tank Mates | Any medium- to large-sized bottom-dwelling fish and larger invertebrates. |
Natural Habitat
The natural habitat of giant danios spans several Asian countries, including India, Myanmar, Nepal, Thailand, and Indochina regions. Their distribution encompasses the Mekong basin and rivers like the Ganges and Mekong.
In their native environment, giant danios are commonly found in streams and rivers nestled among hilly terrains. This is often at elevations reaching up to 1000 feet (300 meters) above sea level.
The fish is native to a tropical climate and are surface dwellers in their habitats.
It prefers areas with abundant aquatic and marsh plants, decaying organic matter, and intricate root systems.
You’ll primarily observe it in shaded, mid-hill clear waters, typically with pebble or gravel substrates. It forms schools near the water’s surface in small, high-gradient upland streams, favoring fast-flowing water conditions.
This danio is currently classified as Least Concernon the IUCN Red List as per the 2011 assessment.
Classification
This fish is scientifically known as Devario aequipinnatus, and it belongs to the family Cyprinidae within the order Cypriniformes.
It is widely recognized by its common names, giant danio, sind danio, and Malabar danio. There is also a wide range of local names around Asian countries.
Fun Fact: Giant danios are great dither fish for cichlid aquariums. As they swim around, big cichlids chase them, which exhibit their territorial and hunting behaviors.
Appearance
If you’re intrigued by the captivating fish, let’s embark on a journey to explore its intricate details and enchanting beauty!
Size
The giant danio, aptly named for its impressive size, can grow to a maximum length of approximately 15 cm (5.9 in). But it usually grows up to 12 cm (4.7 in).
In their natural habitat, these fish are known to grow even larger than their aquarium counterparts.
Color
The body of the giant danio shines with iridescent gold and has electric blue spots and stripes that go from its head to its tail. The fins are light yellow and transparent.
The fish can even display subtle tinges of green or pink on their fins, adding to their charming and diverse appearance.
You can also discover other color variations of the giant danio. One variant has a greyish-blue body with green and yellow stripes and dots.
Another variant has a yellow body (known as Golden giant danios or Yellow giant danios). This is also referred to as the albino member of the group, showing off their unique, pale-yellow hue.
The colors on the female are attractive, but it is paler than the males.
Features
The fish has a long and sleek shape, like a torpedo. Looking closely, you might notice a little fleshy filament near its mouth called a barbel. It has rounded fins, and the tail looks like it’s split in two, creating a forked appearance.
Sexual Dimorphism
Unlike males, female fish are biggerwith round bellies. The adult female fish has a blue stripe running down the center of their body, and it curves upwards toward its tail fin.
In contrast, the males have straight blue stripes that don’t bend in any direction. This distinction in the pattern of their blue stripes helps tell them apart.
Behavior & Temperament
The lively schooling fish thrives in a community. It exhibits behavior akin to playful children – constantly on the move, engaging in games with their peers, and occasionally having little squabbles over food and space.
When in a larger school, it establishes a natural hierarchy, which helps reduce conflicts.
Believed to be slightly aggressive, this species is an incredibly active and energetic swimmer.
In smaller groups, the fish might disturb each other. Its playful antics can sometimes annoy larger or smaller tankmates. This behavior often comes across as aggression, but it’s just its way of having fun.
Lifespan
In an aquarium, with proper care, giant danios can live for 5-7 years. But in the wild, their lives are often shorter due to diseases, predators, and environmental factors.
Author’s Note: About 85% of giant danios exported from India are wild-caught.
Giant Danio Care
If you’re enthusiastic about adding this fish to your aquarium, let’s dive into the specifics of how to provide it with the best care possible!
Tank Size
Since the giant danio needs to stay in groups of at least 5, it requires ample swimming space.
Some say a 30 or 40-gallon tank can work if it’s the long, horizontal type. But in my experience, a 55-gallon tank must always be the recommended minimum.
Remember, it’s better to avoid taking chances.
Additionally, your tank must be at least 36 inches in length to allow all of them to live comfortably.
Water Chemistry
Next up, you must make sure that your tank has the perfect water conditions to help the danio thrive.
- pH Levels: 6-8
- Water Temperature: 72-75 °F (22-24 °C)
- Water Hardness: 5-19 dGh
- Ammonia: 0 ppm
- Nitrite: 0 ppm
- Nitrate: Below 20 ppm
Tank Environment
Your next step is to establish a secure and nurturing environment for the fish. Here’s a guide to help you create the perfect atmosphere for their well-being.
Substrate
Giant danios are primarily surface and mid-level swimmers, so the type of substrate isn’t critical for their well-being. But a dark substrate can enhance the display of their vibrant colors.
To recreate their natural habitat found in hill streams, river gravel or sand is a suitable choice.
Plants
Aquariums filled with live plants are ideal for a group of giant danios. They don’t snack on or disturb your aquatic plants.
Plants offer shade and hiding spots, which act as security for these nervous fish. They will also help keep the water clean by using fish waste as a natural fertilizer.
Plenty of plants also help in securing the eggs if the fish spontaneously breeds.
Floating plants can discourage them from jumping out of the tank, so you may also consider adding a few of them. Here’s a list of plants for your quick reference:
- Guppy grass
- Hornwort
- Java moss
- Anacharis
- Vallisneria
- Amazon sword
- Cryptocoryne
- Water wisteria
- Java fern
- Anubias
Place your plants in the bottom and back of the tank so that the fish gets enough space in the middle for swimming.
Lighting
Provide subdued lighting for the danio’s comfort and to display its vibrant colors effectively.
Since it is a diurnal fish (i.e., they are active during the day), it’s best to keep your tank well-lit during daylight hours. This will help establish their day-night cycle.
Décor
Keep it simple to mimic their natural habitat. Use minimal decor around the tank’s edges. Leave most of the tank empty for swimming. Add caves and driftwood as hiding spots for comfort.
Filtration
Invest in a well-sized filtration system. It will keep the water clear and maintain the necessary oxygen levels.
To further enhance the oxygenation of the water, consider adding air stones to the aquarium. These create bubbles, increasing the surface area for oxygen exchange, which is vital for the well-being of your pet fish.
Water Flow Rate
Create a water flow with some gentle current to mimic the rivers and streams of its natural habitat. It particularly enjoys swimming against moderate water flow.
Fish Care Tip: To maintain a clean and healthy environment for your giant danio, it’s essential to change 20% to 30% of the water volume in the tank every month. This regular water change helps remove pollutants and ensures optimal water quality.
Food & Diet
The species is omnivorous with carnivorous instincts and also a planctophage in its natural habitat. It primarily feasts on exogenous insects, worms, and crustaceans. They have a particular fondness for flying insects.
In captivity, giant danios are quite flexible with their diet. They readily accept various foods, making them relatively easy to feed in a home aquarium.
For a well-balanced diet, consider offering these foods:
- Flakes
- Pellets
- Daphnia
- Brine shrimp
- Bloodworms
- Mosquito larvae
- Vegetable flakes
- Chopped earthworms
- Chironomus larvae
- White worms
When feeding, make sure the food floats on the water’s surface, as they prefer to eat from the surface.
They are most happy with multiple small feedings each day. Provide only as much food as they can consume in approximately three minutes or less during each feeding session.
However, if you can only feed them once a day, give them enough food to eat in about 5 minutes.
Tank Mates
The giant danio prefers company, so it’s best to keep at least 5 together in an aquarium. The more space and companions it has, the happier and healthier it’ll be. If it gets lonely, it may experience heightened stress and increased vulnerability to diseases.
Further, a good company also helps them to accommodate their schooling behavior and foster their natural social interactions and overall happiness.
While selecting tank mates of other species for them, opt for medium- to large-sized bottom-dwelling fish.
Some compatible tank mates for giant danios include:
- Tiger barbs
- Silver dollars
- Rainbowfish
- Tinfoil barbs
- Denison barbs
- Oscar cichlids
- Jack Dempsey cichlids
- Red devil cichlids
- Texas cichlids
- Cory catfish
- Clown loaches
- Agassiz’s dwarf cichlids
- Angelfish
- Gouramis
- Swordtails
- Platies
- Corydoras
- Rasboras
- Bristlenose plecos
- Kuhli loaches
- Cherry barbs
- Harlequin rasboras
- Neon tetras
- Zebra danios
- Dwarf spotted danios
- Clown plecos
- Cardinal tetras
- White cloud mountain minnows
You can safely keep invertebrates like shrimps, snails, and crabs with these species, provided they are large enough not to be considered prey.
Cherry shrimp and mystery snails are a good choice.
Tank Mates to Avoid
Avoid keeping the following in the same tank:
- Slow-moving or shy fish: The danio is a fast swimmer and might harass or stress slower fish.
- Small fish or fry: Giant danios may view smaller fish or fry as potential snacks. So avoid keeping them with very small or delicate species.
- Aggressive fish that can outcompete them: While they can coexist with large cichlids, be cautious about highly aggressive fish that might outcompete them for food and territory, leading to stress or aggression.
- Territorial bottom-dwelling species: Some territorial or bottom-dwelling fish may not appreciate the active nature of giant danios and could become stressed in their presence.
- Fish with flashy or exuberant fins: Be careful when putting them with such fish (bettas and guppies); they might nip fins.
Common Diseases
Giant danios are typically hardy and disease-resistant in a well-kept tank. However, keep an eye out for these issues:
| Disease Name | Causes | Symptoms | Treatment |
|---|---|---|---|
| Dropsy | Viral and bacterial infections, parasites, poor water conditions, stress, improper nutrition, overcrowding | Swollen belly, protruding scales, ulcers, reddening at the base of fins or vents | Isolate the infected fish, maintain perfect water quality, use antibacterial treatments, |
| Hole-in-the-head Disease (Hexamitiasis) | Hexamita protozoans, poor nutrition, overcrowding, low oxygen levels, bad water conditions, stress | Small holes on the body, yellow strings of mucus, loss of appetite | Serve medicated fish food, add Metronidazole directly in the tank, improve water quality, quarantine new fish |
| Ich (White Spot Disease) | Ichthyophthirius multifiliis protozoan, typically introduced by new fish, poor water quality, the addition of infected equipment | White spots on gills, skin, and fins, body scratching behavior, loss of appetite, and clamped fins. | Use commercial treatments, add aquarium salt, raise the water temperature, and maintain water quality, clean tank, use sterilized tools |
| Fin Rot | Bacteria like Flavobacterium, poor water conditions, poor nutrition, overcrowding | Stumpy, frayed, or split fins with white or black edges | Isolate the affected fish, use antibacterial treatments, and improve water quality |
| Gill Disease | Poor water conditions Bacterial, protozoan, or fungal infections | Swollen gills, discolored gill filaments, gasping at the surface, lethargy | Improve water quality, use antibacterial treatments, consider copper treatment for parasites |
| Popeye Disease (Exophthalmia) | Parasites, bacterial infections, poor water quality, or injuries | Bulging eyes, one or both eyes protruding | Isolate affected fish, use antibiotics for bacterial infection, or aquarium salt for injuries |
| Cotton-Wool Disease (Mouth Fungus) | Fungal infections (Flavobacterium), poor water conditions, sudden changes, overstocking | Cotton-wool-like growths, loss of appetite | Isolate infected fish, use antibacterial treatments, improve water quality, and reduce overcrowding |
| Velvet | Oodinium pathogen | Scratching against tank walls, loss of appetite, skin peeling, appearance of yellowish or rust-like dust substance | Maintain water temperature, proper cleaning, use aquarium salt, avoid carbon filters |
| Columnaris | Bacterial Infection | Cotton-like structure around gills, loss of appetite, slow movement, lesions, white, brown, or yellowish gills | Medication through proper drugs and antibiotics, aquarium salt, vaccination, clean water, maintain temperature |
| Swim Bladder Disorder | Poor water quality, bacterial or parasitic infection, stomach swelling, abrupt temperature change | Abnormal buoyancy, curved spine, floating at top or bottom, swollen belly | Clean tank and water, add aquarium salt, maintain temperature, fasting, feed peas, consult a veterinarian |
Quick Tip: Maintain an appropriate fish-to-tank size ratio to keep your fish in optimum health. Do not overcrowd your tank, or it may stress them, leading to weakened immunity. Stress and excess waste generated can create a breeding ground for diseases.
Breeding & Reproduction
Giant danios are relatively easy to breed in captivity, and this can even happen spontaneously in home aquariums.
While not absolutely necessary, a separate breeding tank is often used to protect the eggs and fry from being eaten by adult fish.
Preparing the Breeding Tank
The tank should be preferably 20 gallons or more. Ensure it receives some natural sunlight, as this can stimulate spawning.
Maintain the breeding tank’s water quality so that it closely mimics their natural habitat.
- Water Temperature: 77 to 82°F (25 to 28°C)
- pH Levels: 7.0 or below
Provide fine-leafed plants like Java moss or a spawning mop. These are suitable for catching and attaching scattered adhesive eggs.
Male-to-Female Ratio & Conditioning
A good breeding setup must have a male-to-female ratio of one male to three females.
Feed them live foods like brine shrimp, daphnia, or mosquito larvae to enhance their reproductive readiness.
Courtship Displays & Mating Behavior
Before spawning, the male Giant Danio initiates courtship behavior to attract the female. These include vibrant coloration, increased activity, and vigorous swimming patterns.
Once the male is ready to mate, he will actively chase the female throughout the tank and bump her abdomen.
Other than that, early morning sun rays hitting the breeding tank often trigger spawning.
Egg Release
The actual spawning act involves the female releasing her eggs into the water column. The male, in pursuit, will fertilize the eggs as they are released.
During breeding, females release 5-20 eggs per pairing until as many as 300 eggs are laid. Eggs are typically scattered among plants or a spawning mop.
The eggs are small, adhesive, and often stick to plants or other objects.
Parental Behavior
Giant danios do not exhibit parental care; in fact, they may eat their own eggs. Remove the breeding pair immediately after egg-laying to protect the eggs.
Hatching & Fry Caring
Eggs hatch in about 24 to 36 hours and fry become free-swimming after 48 hours.
Initially, the fry should be fed with infusoria or powdered food until they are large enough to accept brine shrimp or other small live foods.
Breeding Tip: Use an air pump in the breeding tank after the giant danios eggs are laid. It increases the oxygen exchange in the vicinity of the eggs. This further ensures that the developing embryos receive an adequate oxygen supply, leading to proper development.
Quick Buying Tips
- Choose giant danios that swim actively throughout the entire tank. Avoid fish that appear lethargic and hide.
- Inspect closely for any white spots, blemishes, torn or ragged fins, or bulging eyes. They should exhibit regular, rhythmic gill movements to take in water and oxygen. Rapid or labored gill movement may indicate respiratory issues.
A word from FIA
The giant danio is a captivating species that enhances the beauty of your aquarium. It is an excellent choice, particularly for those new to the world of fishkeeping.
Its adaptability and resilience make it a rewarding addition to any aquatic environment.
If you’ve found this article informative and inspiring, we encourage you to share it with fellow enthusiasts. Let them also appreciate the joys of raising this danio.
However, if you have any more questions or need further assistance, please don’t hesitate to reach out to us via email.