How are common general fish medications used? Detailed usage guide

1. Quicklime

It can be used for pond clearing and disinfection, and can raise the pH of the pond water, improving the pond bottom substrate and water quality.

2. Formalin (formaldehyde)

A 30 ppm solution for a 24-hour soak can kill Trichodina, Chilodonella, Dactylogyrus and Ichthyophthirius, etc.; a 250 ppm soak for 1 hour, or 100 ppm for 3 hours, can treat Gyrodactylus and other protozoa; using a 3%-5% solution to soak spawning nests for 2-3 minutes can prevent saprolegniasis; applied as a mixture with malachite green to the whole pond, it can treat ichthyophthiriasis; at a concentration of 150 ppm for about 5 hours, fish begin to die. Poisoned fish show faded body color.

3. Malachite green (basic green)

Apply a 1% solution to the wounds of brood fish to prevent infection; a 66 ppm solution soaking large fish suffering from saprolegniasis for 30 seconds is effective; at a water temperature of 8-9°C, 0.5 ppm used continuously for 3 days can cure ichthyophthiriasis in carp; broadcasting 0.1-0.2 ppm over the whole pond can effectively prevent and treat saprolegniasis and can also kill Trichodina; at low temperatures, using it together with methylene blue can improve the efficacy. Using 0.05 ppm basic green together with formalin can treat Chilodonella; used twice a day it can treat ichthyophthiriasis; soaking at 0.5 ppm for 2 hours, repeated several times, can kill Ichthyophthirius; in addition, it has a killing effect on Trichodina, Ichthyobodo, Gyrodactylus and Chilodonella.

4. Potassium permanganate

Soaking method: at a water temperature of 15-20°C, using 20 grams of potassium permanganate per cubic meter to soak diseased fish can cure lernaeosis in grass carp and carp; soaking diseased fish in 20 ppm potassium permanganate for 15-30 minutes is effective for killing Gyrodactylus, Dactylogyrus, Trichodina and Chilodonella.

Smearing method: prepare potassium permanganate as a 1% aqueous solution and apply it to the affected areas of diseased fish; it can cure Sanguinicola infestation in carp.

Whole-pond broadcasting method: use a 4-5 ppm concentration together with 7‰ salt to treat saprolegniasis, protozoan and crustacean fish diseases; change the water after 3-5 days to remove the salt; using 0.1 ppm potassium permanganate together with 0.25 ppm copper sulfate can treat Chilodonella.

5. Bleaching powder

Pond clearing method: use a 20 ppm concentration to clear the pond with the water in place.

Whole-pond broadcasting method: use a 1 ppm concentration to prevent and treat red-skin disease, gill rot and hole-in-the-body disease; if used continuously for 3 days, it can treat white skin disease and white head and white mouth disease.

Hanging basket method: during the disease outbreak season, hang 3-6 bamboo baskets at each feeding platform, with about 100 grams of bleaching powder placed in each basket, which can provide preventive effect.

6. Trichlorfon

Soaking method: use 90% crystalline trichlorfon at a concentration of 20-40 ppm, soaking fingerlings at 10-15°C for 10-12 minutes, which can kill parasites such as Dactylogyrus, Sinergasilus, Lernaea and Gyrodactylus.

Whole-pond broadcasting method: 90% crystalline trichlorfon at a concentration of 0.2-0.3 ppm, used once every 3-5 days, for 3 consecutive times, to treat lernaeosis; 2.5% trichlorfon powder at a concentration of 1-4 ppm or 90% crystalline trichlorfon at a concentration of 0.2-0.5 ppm can kill Dactylogyrus, water centipedes, mussel shrimp and fish lice, etc.

Toxicity: the toxicity of trichlorfon varies with different fish species, @#@241@#@the safe concentration for fish is 0.18-0.54 ppm; for sea bream and crucian carp it is 1.8-5.7 ppm; the lethal concentration range for fish lice larvae and adults within 12-24 hours is 0.2-0.3 ppm.