Live bait is considered critical for success by the anglers. Whether croakers, cocahoe minnows or mullet are used, live bait must, by definition, be kept alive to be used.

That’s why Shane Zeringue has installed a high-tech system at his camp to do just that.

Under his boat shed, he has two 200-gallon live-bait tanks. One is simple. It sucks water from the canal (which connects directly to the bay), forcing it through the tank and back out into the canal.

The other tank is a closed system, meaning it recirculates its own water without any connection to an outside source. Large numbers of any fish or crustacean in such a tank would quickly die from the ammonia and nitrites in the animals’ own wastes.

What makes Zeringue’s system work is a biological filter, essentially a place for bacteria that “eat” ammonia and nitrites to thrive.

In his system, the bacteria grow on the surface of plastic shavings inside a plastic barrel. Water from the bait tank flows through the medium by means of an air pump, the bubbles from which lift water up a pipe, much like the plastic aquarium filters of old. The air pump is large enough to supply air to three air stones in the tank, as well.

A wrinkle that he added is a method to cool the water using a room air conditioner; cool water holds more oxygen than warm water.

He had a technician pull the condenser from the air conditioner and submerge it in the tank. The air conditioner is plugged into a thermometer that turns the AC off and on to keep the water between 70 and 72 degrees Fahrenheit.

The thermometer and plastic shavings are available online from Aquatic Eco-Systems (www.aquaticeco.com), an aquaculture supply firm.

Zeringue’s system can hold 300 to 400 croakers for an extended period of time.