Breeding the Blue Dwarf (Badis badis)

Author: Maddy Hargrove

An uncommon aquarium fish, the blue dwarf is a colorful animal that makes an excellent addition even for nano aquariums. Learn how to breed these blue beauties in your own home.

Introducing Blue Dwarfs

We are all familiar with guppies, tetras, discus, and goldfish, but these are only a few of the tropical and coldwater fishes that have become common in home aquariums worldwide. Many of us have enjoyed and appreciated them for their unique body forms and interesting social behaviors at one time or another, but sometimes we stray from the norm and attempt to provide care for a species we are completely unfamiliar with. There are many fishes that can make great additions to your tank, even if they are more obscure in the aquarium trade.

Nandidae, an interesting and highly unusual family, includes one such fish: Badis badis. Though it is sometimes called the chameleon or blue dwarf, it is often referred to simply as a badis. There are at least three subspecies: B. b. badisB. b. burmanicus, and B. b. siamensis. While two of these are usually bluish gray or brown in color, B. b. burmanicus tends to have a red tint. Their colors will change to suit the environment around them, however. And if the fish is healthy, the body will have a speckled look.

Native Habitat

The family Nandidae has few members, but they are all beautiful in appearance. The badis, the South American leaf fish (Monocirrhus polyacanthus), and the Asian leaf fish (Nandus nandus) are examples. It is believed that Nandidae represents a group of ancient fishes that once spanned the entire globe, but today’s few species are found only in Asia, Africa, and South America.

In the wild, these fish live in slow-moving ponds and streams. They are experts at hiding for survival and tend to spend much of their time hanging out with dead leaves and twigs. All members of this family can change color to smoothly blend in with their surroundings. You really have to look closely to spot one that does not want to be seen.

Social Habits

Members of the Nandidae family are generally slow movers that surprise their prey by using the art of camouflage and subterfuge. The badis is famous for reversing the tables on other fish that might see it as a delicious meal—it is capable of killing and eating fishes almost twice its size. The related leaf fish is known to drift suspended in the water so it resembles a dead leaf, waiting patiently until unsuspecting prey moves within striking range.

Fortunately, when provided proper diet, the blue dwarf is not required to follow its family’s aggressive feeding habits. This fish, which attains a length of up to 2½ inches, is generally peaceful in nature unless it is provoked by larger fishes or disturbed during spawning periods. It was once classified as a cichlid and will usually mix very well with dwarf cichlids that have similar requirements and peaceful natures.


Hobbyists able to obtain the elusive blue dwarf usually have no trouble breeding it. The fish will spawn quite regularly when it is living in a species tank. Blue dwarf males are more colorful than their female counterparts, and females have a convex belly while the males have a more concave one. The female is usually heavier and fuller bodied than the male.

Water changes are very important in the conditioning process. Good conditioning will also help guarantee spawning success. In the wild, seasonal rains are one of the signs that usually signal the start of the breeding season. During the rainy season, the waters of the dwarf’s natural habitat will become softer as they are diluted and the concentration of dissolved wastes drops. You can duplicate this conditioning effect in your spawning tank through frequent water changes (about 15 percent per day for breeding). Clean, de-mineralized water will also help to stimulate their seasonal spawning cycle. A drop in barometric pressure is another natural spawning trigger. In fact, many species of fish will breed during or before a storm.

Both male and female are often ready to spawn when they reach a length of 1 to 1½ inches. For breeding in a species tank, it is recommended that at least six females be kept with every two males. Beautiful colors have been produced recently through selective breeding. When ready to breed, the male will begin to display a more intense color. During spawning, the male will embrace the female and her eggs will be expelled.

After spawning, the females should be removed from the aquarium for their own safety. There are certain cases where the females can be left in the spawning tank if plenty of hiding places are available, but it is always safer to remove them because males can become very aggressive after spawning is complete. You don’t want to lose your prized females by trying to beat the odds, so remove them.

The spawning tank should employ sand or fine gravel as a substrate. The blue dwarf prefers darker gravel, which will help it feel more relaxed and less threatened. Plenty of hiding places need to be provided in the spawning tank for privacy. Large rocks can be used to build small caves, ledges, and walls. Many hobbyists have used flowerpots or coconut shells as a spawning site with great success. The eggs will usually be laid on the underside of whatever surface is provided.

A sponge filter is ideal for the spawning tank. A sponge filter will not cause excess current like large power filters. Heavy currents can damage newborn fry if they end up getting blown across the tank. A good sponge filter will provide biological filtration and prevent the fry from being sucked up into the filter system. The microbes that grow on and in a sponge filter also make great supplemental food for the fry.

The breeding tank should be at least 20 gallons, and the water temperature needs to be maintained around 75°. Keep the lighting to a minimum when breeding these fish so they don’t become startled. Water hardness should be moderately soft, and the pH should remain just slightly acidic. A tight-fitting hood will keep your excited and active blue dwarves from jumping out of the spawning tank as well as prevent dirt and dust from entering the water. A good hood will also keep heat loss to a minimum.


During and prior to the spawning period, live food is a must to ensure that proper conditioning occurs. These fish are highly carnivorous in the wild, and live and frozen foods are most appreciated by the species. They will not do well on dry food alone, though they may learn to accept it.

Raising the Fry

After the eggs are laid (up to 100 total), the male will guard the spawn until they consume their yolk sacs. When the young begin swimming on their own, they will feed on microorganisms, but they will be able to take larger foods, such as rotifers, liquid fry food, and baby brine shrimp, about a week later. The fry should be fed at least three times per day. The fry will usually cling to tank decorations, such as rocks or plants, and snatch up food as it moves past them. During this initial period of growth, the youngsters are usually safe from their parents.


In order to keep track of your fish’s breeding behaviors and new fry, you should seriously consider keeping an accurate running record in a log or notebook. Each particular specimen can be easily logged in and recorded as you purchase it. Information such as age, sex, species, color, unusual traits, size, personality, health record, and mating habits can be added to the log as you go along.

Photography is another great method for capturing information on growth, disease, spawning rituals, and fry development that may be passed over in a written record. Pictures taken periodically and included with your written data record are a great way to keep good tabs on your progress in the hobby.

Making New Friends

There is nothing wrong with keeping a certain species you think the world of, but an important part of the hobby is to grow and learn whenever possible. If we don’t experiment a little with fresh ideas and new species, we can become stagnant and open the door to the possibility (no matter how remote) of losing interest in our hobby.

One of the best ways to grow and learn is by keeping new species. I remember a long time ago when a friend donated a pineapplefish (Monocentris japonica) to me because he was moving and unable to transport his favorite pet. This fish quickly became one of my all-time favorites.

The next time you are down at the pet shop or placing an order for new fish, you might want to give the attractive B. badis a try. You may find yourself fascinated, intrigued, and hooked.