What is your electrofisher ammeter telling you? The obvious answer is that it is indicating amperes of electrical current flow, the movement of electrical charges past a point or surface. But not all electrofisher ammeters display the same measure of current, and that can and does lead to confusion.
For instance, one backpack electrofisher has an ammeter which displays continuous direct current (DC) current draw from the battery even though the output into the water is pulsed direct current (PDC). Another backpack unit displays only output average current. Still others display output peak current. For electrofishing, the primary concern for fishing is the output peak current. So why display DC current from a battery or output average current? Those measures are informative in terms of battery life and of loading on the unit. They tell you about the operation of the unit, which is important, but they may tell you little about its fishing effectiveness. Similarly, some boat electrofishers have ammeters which display alternating current from the generator, a measure of generator loading.
The following situation is fairly common. Someone has been using a Smith-Root GPP boat electrofisher which had only an “average” ammeter. Then they begin using an ETS MBS or an MLES Infinity boat electrofisher. The latter two units have ammeters which display output peak current. They were successful fishing at a given body of water, with its inherent water conductivity, using the GPP unit at 5 amps of current showing on the ammeter. With the new unit, they adjust the voltage so that 5 amps of current shows on the ammeter. What is the result? They don’t catch fish and they conclude that their new boat electrofisher is malfunctioning. The real explanation is that the GPP and the ETS or MLES ammeters are displaying different units of current. Five amps of average current on the GPP may equate to 20-25 amps of peak current. The solution is to increase the voltage on the new unit so that the peak current is about 20-25 amps. Use that as a start and then fine tune the voltage adjustment for fishing threshold, the minimum needed for full success, and go fishing. Let me say that newer GPP units have peak-reading meters for voltage, current and power. But there are many older units still in operation which have only an average ammeter. The ETS meters display peak voltage and current. The MLES meters display peak voltage, current and power. If there were only one meter on a boat electrofisher, my choice would be an output peak ammeter.