You will have to experiment in your own pond to determine when you have reached the right amount. With an overabundance of forage fish, removal of 50 to 100 pounds per acre may be necessary to reduce the numbers to a level where the bass can control them. When seining or fish traps are not practical as population reduction methods, the forage fish population may be reduced using a fish toxicant. Rotenone, long used as an insecticide, is a common ingredient in fish toxicants. Read and follow label directions for proper use of fish toxicants.
Rotenone is a restricted-use pesticide.
You must be licensed to purchase and use it. The information provided here is intended to clarify and supplement that which is found on the product label. In situations where the intent is to reduce, but not eliminate, the fish population, usually no more than half the shoreline should be treated at one time. Water temperature influences the effectiveness of rotenone. It acts more slowly at lower temperatures.