A black angelfish is 4 yuan. The black angelfish is native to the Amazon River in South America. The fish body is rhombus-shaped, extremely flattened on the side, the rear edge of the caudal fin is straight, the rays of the dorsal and anal fins are extended backwards, and the upper and lower sides are symmetrical, like an open sail. The pelvic fins are long and filamentous. From the side, it looks like a swallow flying in the air, so it is also called swallow fish. Angelfish has no bright colors. The base color of the original fish is silver white, the back is golden yellow, and there are four black horizontal stripes on the side of the body. The first one passes through. Eye sockets, the second at the front edge of the base of the dorsal and anal fins, the third from the end of the dorsal fin to the end of the anal fin, and the fourth at the base of the caudal peduncle.

The black angelfish dorsal and anal fins are light yellow, and the caudal fin is transparent and covered with black Longitudinal stripes and red eye sockets. Body length up to 150 mm, body height up to 200 mm. Angelfish are gentle in temperament and elegant in manner. They like to swim in the middle of the water. They often stop in the water and have a quiet habit. It is best to keep them in a single tank. There are no strict requirements for water quality, and they like soft water with weak acidity. Angelfish can live in a water temperature of 20 °C, but the water temperature is low for a long time, and it is not good for growth and susceptible to disease. The most suitable temperature is around 26 °C.