Blind tetra (Anoptichthys jordani) is a native of Mexico (the state of San Luis Potosi) and in vivo it can only be found here. Her element is the warm lakes of the cave type. Due to the lack of light in underground water bodies, the tetra, as well as other species of animals leading an underground lifestyle, has no eyes. Instead, the fish has two shiny silver scales. At the same time, the fish is well oriented in any locality, reacts immediately to the appearance of food and other pathogens, thanks to the well-developed lateral line organs. The tetra has a tall, highly compressed body on the sides, the average length of the fish is 8 cm. Males are usually smaller and slimmer than females with a full belly. Color tetra pigmentation is completely absent, and capillaries translucent through thin skin give it a reddish-pink color. Sufficiently developed tetra fins are also colorless, almost transparent, but only during spawning in males they acquire a red tint. The tail of the fish is bifurcated, rounded at the tips.
A blind fish is not picky about food: it eats not only live, but also dry food. For the health of the fish, it’s more useful to treat it with a pipe maker and Daphnia more often. You can also give vegetable feed, bread, scalded cereals and scraped meat. When feeding due to blindness, the tetra can attempt to attack other fish, but this is not due to its aggressiveness, but during the search for a new portion of food.
Maintenance and care
Tetra behaves peacefully and calmly in an aquarium. It is better to select plants for her with hard leaves so that she does not bite them. The water temperature should be maintained at a level of 20–28 degrees and have sufficient rigidity. Bright lighting is not needed. In addition, in the aquarium you need to arrange more nooks and crannies. Tetra moves throughout the aquarium, but mostly swims closer to the bottom. For several fish, an aquarium with a capacity of 80 liters is enough. Tetra are schooling fish, usually moving in small groups. They have a kind of locator that helps to circumvent all obstacles and quickly find food. Due to the specific content of blind fish, it is better not to plant other fish species.
In captivity, tetra reproduces without any problems. She reaches puberty in a year and a half. First, a couple of healthy producers or one male and two or three females are planted in different aquariums, while feeding is strengthened, as the appetite of the fish before spawning noticeably increases. Two weeks later, the selected fish are planted for spawning. To do this, prepare spacious spawning grounds measuring 30 x 20 x 20 cm with fresh water and low light. Fine sand or gravel is placed at the bottom, and moss or willow roots are laid on it. During the mating season, tetras behave very interestingly. They immediately find themselves in different corners of the aquarium. Then they meet and rise to the surface together, slightly clinging to each other, and then diverging in different directions. The female gradually swallows from 500 or more eggs, which fall to the bottom and stick to the plants, after which the male immediately fertilizes them. Subsequently, he carefully looks after the offspring. The ripening of eggs lasts from 36 to 72 hours, depending on the temperature. When they start to hatch, it is better to drop the male out of the aquarium. After three days, the fry begin to swim independently and eat intensively. They are fed with live dust and infusoria. To avoid eating each other, kids need to be sorted. The young grows very quickly and at the age of six months they become sexually mature.