What Are the Living Habits of Loaches? A Detailed Explanation

The loach is a small bottom-dwelling fish, generally living in still or slow-flowing water with a muddy bottom, and it can breathe through its gills, intestines, and skin. The loach is a warm-water fish, living at water temperatures of 10-30°C, with the optimum water temperature being 25-27°C. The loach has a very high tolerance for low dissolved oxygen and can survive for a relatively long time after leaving the water. The loach is an omnivorous fish, mostly coming out at night to prey, feeding on plankton, aquatic insects, crustaceans, debris of aquatic higher plants, and algae, among others.

1. Habitat: The loach is a small bottom-dwelling fish, generally living in still or slow-flowing water with a muddy bottom, often appearing in the surface layer of mud rich in plant debris at the bottom of lakes, ponds, ditches, and paddy fields, and it almost never swims to the upper and middle layers of the water body.

2. Water temperature: The loach is a warm-water fish, living at water temperatures of 10-30°C, with the optimum water temperature being 25-27°C. When the water temperature rises to 30°C, it burrows into the mud to aestivate, and when the water temperature drops below 5°C, it burrows into the mud to a depth of 20-30cm to overwinter.

3. Oxygen: The loach has a very high tolerance for low dissolved oxygen. In addition to relying on its main respiratory organ, the gills, it can also directly breathe oxygen from the air through auxiliary respiratory organs such as the intestines and skin. Moreover, the loach can survive for a relatively long time after leaving the water; in a dry bucket, a juvenile loach with a total length of 4-5 cm can survive for 1 hour and still move normally when returned to the water.

4. Feeding habits: The loach is an omnivorous fish, mostly coming out at night to prey, mainly feeding on plankton, aquatic insects, crustaceans, debris of aquatic higher plants, and algae, among others, and sometimes also ingesting bottom humus or mud residue.

5. Reproduction: The loach is a dioecious fish that spawns in batches and fertilizes externally. It usually reaches sexual maturity at 1-2 years of age, begins breeding every year in April (at a water temperature of 18°C), and spawns in shallow water less than 30 cm deep among aquatic plants. The newly hatched larvae often live scattered and do not form groups.