... b. It can improve the fecundity, hatchability and survival rate(10%---30%),and promote growth of the aquatic products. c. It ... poor, use agents 2—3kg per acre every 7 to 10 days, 15 to 30 days once after the water quality ... effects. e. Hot summer weather, pay attention to the proper aeration tank, and with the use of agents, the effect is more ...