Acute toxicity of potassium permanganate to channel catfish fingerlings

Abstract

The 96-h LC50 of potassium permanganate (KMnO 4) applied as a single dose to fingerling channel catfish Ictalurus punctatus in aquaria increased from 4.5 to 17.6 mg/l as the chemical oxygen demand (COD) of the test waters increased from 21 to 118 mg/l. When the total amount of added KMnO 4 was divided into four equal doses applied at 30-min intervals, the 96-h LC50s ranged from 9.0 to 25.6 mg/l within a similar range of COD values. Relationships were also developed for the “15-min KMnO 4 demand” of the water, and COD values with the 96-h LC50 of KMnO 4. The 15-min KMnO 4 demand was found to be a relatively reliable predictor of KMnO 4 toxicity.