There are two quick and simple ways to check to see if your oxygenator is working properly or not.
First, you will want to make sure that all your power connections and connections to your switch are intact and there is 12 volts of power going into the connection attached to your unit.
Second, turn the power switch on for your oxygenator and, under low light, look at the unit with the livewell filled with enough water to cover the unit. Just off from the center of the unit is a green LED indicator light that only comes on when the oxygenator’s electronics are working in a complete circuit.
The other thing to check while you’re doing this test is for a steady stream of bubbles that will come from the oxygenator during the first 60 seconds of turning it on -- this should be a steady flow after the first minute.