The craterfish can grow up. The adult craterfish is larger, spindle-shaped, up to 10 to 15 cm long, with a large head, slightly taller and slightly flatter body, fat and strong. The biggest feature is that it opens its mouth wide, with a mouthful of blood red, hence the name Hukou fish. The calamus does not have strict water quality requirements, and can live in the water temperature of 20 to 30 degrees, and the optimum growth temperature is 23 to 25 degrees. Not choosing food, but love to eat animal bait.

The flamingos are ferocious and should not be mixed with other tropical fish. Under the back of the operculum is a dark spot with a green edge, surrounded by spots and stripes of blue and other colors that gleam in sunlight. The eyes are black, and the rims are green and glowing. The fins are reddish-brown with dark edges and shimmering blue stripes.