A 230-volt, 180-cycle alternating current; a 115-volt, 60-cycle alternating current and a 115-volt direct current were used to attempt to kill intermediate-size bluegill, Lepomis macrochirus, Rafinesque, without harming largemouth bass, Micropterus salmoides (Lacepede). Bluegill and largemouth bass were placed in screen pens in concrete ponds and exposed to different voltages, electrode types and exposure periods. No largemouth bass were killed during exposure periods which killed 75 percent of the bluegill. The 230 volts killed more bluegill than 115 volts A.C. or 115 volts D.C. However, 230 volts A.C. did not kill sufficient percentages of bluegill with short (8-10 second) exposures.