Extended gills like that is an indication of gill disease or low oxygen levels in water. There may be other reasons, but those two stand out.
Fenbendazole is safe to dose orally, however, oral anthelminthics to treat external parasites isn't very effective, external baths work better. In the case of fenbendazole though, I think I mentioned, can have toxicity issues when dosed in the water.
You cannot just add fenbendazole to some food, the dose is very specific: 25 to 50 mg/kg of fish weight, fed daily for 3 days at the low dose or weekly for 3 weeks at the high dose.
Jay
Fenbendazole is safe to dose orally, however, oral anthelminthics to treat external parasites isn't very effective, external baths work better. In the case of fenbendazole though, I think I mentioned, can have toxicity issues when dosed in the water.
You cannot just add fenbendazole to some food, the dose is very specific: 25 to 50 mg/kg of fish weight, fed daily for 3 days at the low dose or weekly for 3 weeks at the high dose.
Jay