Submitted to: Journal of the World Aquaculture Society
Publication Type: Peer reviewed journal
Publication Acceptance Date: 8/25/2003
Publication Date: 3/1/2004
Citation: Straus, D.L. 2004. Comparison of the acute toxicity of potassium permanganate to hybrid striped bass in well water and diluted well water. Journal of the World Aquaculture Society. 35(1):55-60. Interpretive Summary: Potassium permanganate is a widely used chemical in aquaculture where it is used to kill parasites on fish. Hybrid striped bass production is a rapidly growing industry, but there is no data on the toxicity of this chemical. We exposed 5-month old hybrid striped bass to potassium permanganate in aquaria filled with filtered well water or filtered well water diluted with deionized water. We found the amount that would be toxic to the fish, but we also found that the potassium permanganate was more toxic in the well water (higher alkalinity and hardness) than in the diluted water; the difference was statistically significant and this is the first research to suggest why this happens. Our results indicate that hybrid striped bass juveniles can tolerate concentrations of potassium permanganate that are recommended to kill parasites. Such treatments in low alkalinity/hardness waters are safer than treatments at higher alkalinity. This information is important to fish farmers and aquaculture extension agents, and will save the farmers money from fish losses.
Technical Abstract: The acute toxicity of potassium permanganate (KMnO4) to many species of fish has been studied; however, there is no data for hybrid striped bass (female white bass Morone chrysops x male striped bass M. saxatilis). Hybrid striped bass juveniles were exposed to KMnO4 in a series of static toxicity tests in waters composed of filtered (75 µm) well water or filtered well water diluted with deionized water. Estimates of mean 24-h LC50 (median lethal concentration) were 4.47 and 2.97 mg/L KMnO4 in waters having total alkalinities of 109 and 213 mg/L (as CaCO3), respectively. These values were significantly different by the Student-Newman-Keuls means comparison test. Data from the present study demonstrate that the acute toxicity of KMnO4 to hybrid striped bass juveniles is lower in waters of lower total alkalinity and total hardness. The results indicate that hybrid striped bass juveniles are tolerant to therapeutically relevant concentrations of KMnO4 and such treatments in low alkalinity waters are safer than treatments at higher alkalinity.