Anabantids are the family of labyrinthic fish. They possess unique accessory organs for breathing atmospheric air, and are consequently not so effortlessly affected by overcrowding.

The name labyrinth is derived from the intricate network of capillaries in the auxiliary breathing apparatus, which is comparable to a lung in animals. These capillaries are brought into contact with air really taken from the atmosphere.

Breathing isn’t the slow rhythmical procedure of the regular lung: oxygen is absorbed from a bubble of air taken into the mouth, retained for a although, and then expelled via the gills. A fresh bubble is taken in simultaneously with the expulsion of the old one.

Bubble nesters don’t breathe continually in this manner. Conditions of environment, oxygen content of water, and so on, all affect the use of the secondary organ. They’re not a particularly big family, and most of them are very suitable for aquarium use. As a matter of interest Ospkronemus gourami, one of the largest gouramis, attain a weight of over 20 lb.

As most of the Anabantids are bubble nesters, and breed a lot to the exact same pattern, the following description on breeding could be taken usually, any peculiarity to a species will probably be covered under the species heading to save repitition.

The nest is built by the male, either in a corner of the aquarium, under floating plants, or even under a single leaf. The fish rises to the surface, takes in a mouthful of air, and envelopes it in a Sticky saliva-like fluid, which, when expelled, floats to the surface. By continuing this action the bubble nester forms a dome shaped mound of sticky whitish bubbles.

At breeding time the species generally becomes pugnacious which might result in the death of one of them, and it generally turns out to be the female. For this reason your breeding tank should be thickly planted to provide a refuge to the female. Breeding pairs should be roughly the exact same size, and well fed on live foods. They take very well to dry foods, but prefer something moving.

When the male starts to develop the nest, you know he is ready to breed. If the pairs aren’t already together, it is time to introduce them by putting the male into the tank already occupied by his mate. You are able to recognise courtship by the heightened colour and activity of the male, who uses every wile to attract the female beneath the nest. Eventually she succumbs to his charm. Should she be slow to respond he becomes impatient, tearing her fins and attacking her in a most pugnacious manner. This, of course, is when she is most likely to meet her death. There’s naturally a certain quantity of boisterousness during this period, but should it turn out to be likely to result in death, removal of the male is advised. Give them an additional trial at a later date.

In a regular courtship, when the female is under the nest, the male wraps himself around the female in a nuptial embrace until the spawn is released.

This is instantly fertilised, and drops to the bottom of the tank. Now the male picks the eggs up and blows them into the sticky mass of bubble where they remain.

The spawning consists of repeated embraces and insertions of eggs into the nest, which will eventually number between 100 and 500. At this stage, the female should be removed, for the eggs are now cared for by father, who will resent any interference from her, charging tier away from the vicinity of the nest.

During the next two or 3 days the nest will have the undivided attention of the male, who will renew burst bubbles and replace eggs that fall. The nest will turn out to be noticeably larger.

In approximately two days, the eggs will hatch. The young will then be no much more than small black dots. Some will fall from the nest, only to be rapidly returned by the ever-vigilant father. After about 3 days, the yolk-sac will probably be absorbed and you’ll see the fry swimming about just below the surface. At this stage you should feed infusoria. The fry will now turn out to be much more active, and spread much more widely around the tank clinging to the glass, and also the job of keeping them together will probably be much more challenging for their hard-worked parent.

As the fry develop so the male will lose interest. He is then very likely to forget all of the trouble he has taken to protect them, and eat them, and it is at this time he should be removed. You are able to now rear the fry on infusoria followed by micro-worm, etc.

You’ll find that a cover over the aquarium prevents evaporation of the nest and protects the fry from draughts when they’re at a critical stage of their development, but care should be taken that the cover is suitably tilted to permit condensation to run back into the tank away from the nest, otherwise drops of water falling on the nest will break it up.