Callichthys

Callichthys is the species that gives its family its name. Its slender, cylindrical body is armored on each side with two rows of bony plates; its color ranges from dark gray–brown to blackish, its head is broad and flat and its tail is rounded. Adults reach 15–18 cm in the aquarium. It can take oxygen from the air through its gut and can crawl short distances over damp ground from one puddle to another; for this reason it has a strong tendency to escape from the aquarium. It is nocturnal and mostly hides during the day.

• At least 150 liters for a single fish or a small group; a base length of 100 cm or more.
• A tight-fitting lid is essential; cable and hose openings must also be covered.
• Sand or rounded gravel; roots, caves and shaded hiding places.
• 22–28°C; it adapts to a wide range of pH and hardness; strong filtration is recommended.

Omnivorous with a hearty appetite. Large sinking tablets and granules, frozen bloodworms, worms and pieces of shrimp are eaten eagerly. Because it is nocturnal, it is best to feed after the lights go out.

Generally peaceful toward other fish; it hides during the day and forages on the bottom at night. It can be kept singly; a small group also works in a large aquarium, but the male can become grumpy while guarding his bubble nest during breeding.

Good companions: medium to large peaceful fish: large tetras, silver dollars, angelfish, mild-tempered cichlids, plecos.

Avoid: dwarf shrimp, small fish that fit in its mouth, aquariums without a lid or with openings.