An electrofishing controller includes a power input, an output and a user interface for receiving configuration information from a user. The controller further includes control circuitry for receiving electric power from the power input, generating an electric waveform with characteristics defined by the configuration information, and communicating the electric waveform to the output. The control circuitry is configured to automatically adjust the electric waveform in response to changes in an electric load on the output, and to automatically restore the electric waveform when the electric load returns to a normal operating level. The control circuitry is further configured to automatically reconfigure a power circuit in response to changes in the configuration information received from the user, including changing physical connections between physical components of the power circuit.