Eels grow very slowly. Eels can only grow up to four or two or half a catty a year, less than 30 cm, generally more than 20 cm, even if your breeding technology is high. The young eel just emerging from the membrane is 1.5 cm long, the first winter eel is 27-44 cm long, the second winter eel is 45-66 cm long, and the big eel is 70-80 cm long and weighs more than 1.5 kg.