Clever Use of Table Salt to Prevent and Treat Diseases in Grass Carp Farming

Table salt has a strong insecticidal and sterilizing effect, and is a commonly used drug for preventing and treating many fish diseases, especially bacterial, fungal, and parasitic fish diseases, with remarkable results. The prevention and treatment methods are described below.

   1. Prevention and treatment of bacterial fish diseases   Soak and wash fingerlings over 3 cun in 3% salt water for 10-15 minutes, or sprinkle salt water over the whole pond at a concentration of 11-22.5 mg/L, with a water depth of 1 m, using 7.5-15 kg of table salt per mu, to prevent and treat grass carp branchial rot and red skin disease. Mixing 2.5% table salt into compound feed can prevent and treat grass carp enteritis. Using trichlorfon together with table salt can achieve a 100% effective prevention rate against the above three diseases of grass carp, with an early-stage cure rate of over 90% and a mid-stage cure rate of about 80%. The method is to sprinkle quicklime blocks over the whole pond, using 20 kg per mu at an average water depth of 1 m, then immediately use a sprayer with the screen removed to spray a mixture of 90% crystalline trichlorfon and table salt over the whole pond, at 0.5-0.7 mg/L trichlorfon and 5-7 mg/L table salt. In the early stage, one treatment can cure it; in the mid stage, 2-3 consecutive treatments, once every other day, can cure it; for prevention, once every 30-50 days. To prevent and treat enteritis, a small amount of the mixture can be sprayed onto the green fodder in the grass rack for a better effect.   2. Prevention and treatment of saprolegniasis   Overwintering fingerlings or adult fish often suffer from saprolegniasis due to injuries from manual handling, and can be cured by soaking and washing in 30% salt water for 10-15 minutes.   3. Prevention and treatment of various parasitic diseases   When summer fry with parasitic diseases are soaked and washed in 3% salt water, all Chilodonella die within 1 minute; all Cryptobia branchialis die within 5 minutes; all Trichodina, Ichthyobodo, and Ichthyobodo necator die within 10 minutes. For fingerlings over 1 cun, the soaking time can be appropriately extended. When summer fry with parasitic diseases are soaked and washed in 1.7%-2% salt water for 30 minutes, all Gyrodactylus and Dactylogyrus die, and all fish lice fall off. For gas bubble disease in fingerlings, drain one third of the original pond water, then add fresh clean water, and then sprinkle salt water over the whole pond at a concentration of 5-7 mg/L to cure it.