STAYING ALIVE: Large pumps are used to move water through live wells to keep the catch breathing

You can be politically incorrect and eat up all the fish that you catch. Or you can be more with it and do what the ‘in crowd’ in angling does. Catch and release your fish, that is. But there’s a method to it. You just can’t bungle it and end a life. Ask the experts and get clued in.

“In the catch-and-release method of angling the fish is caught, kept in a live well and then released back into the water,” explains veteran angler, Somnath Ganguly of South Sinthee Anglers Club in Calcutta. But the trick is to keep the fish alive and healthy. “To ensure that your prized catch stays alive and well, what you need is a good aerator,” he adds.

An aerator is to a fish, what a snorkel is to us. “So long anglers had a common belief that large live wells are required to sustain a large quantity of fish,” endorses another veteran, Mihir Dutta of North Calcutta Angler’s Association, “and large pumps are needed to move a lot of water through the live well to keep the bait and fish alive”. But that’s passe. Anglers now hold that it all depends on the effectiveness of the aerator and not on any other factor. “If an aerator can provide enough oxygen in the water for the fish to breathe, it doesn’t matter how much water surrounds the fish, he adds. “The only desideratum is that the water must be changed occasionally in live wells to remove ammonia caused by fish poop.”

ABC of aeration:

There are two major considerations in aeration:

a) The gentleness and direction of water flow: Delicate bait such as shad, greenbacks, and white bait will not survive a day of fishing unless the waterflow in the live well is soft and gentle. Turbulent water will damage the bait and force them to work against the current. Ideal waterflow within a live well should be approximately 1 to 2 MPH and in a circular motion. This will allow fish to school and provide a smooth flow of water over and through their gills. If the water flow is excessive, the bait as well as the fish will tire quickly.

b) Size and number of air bubbles:

Take a look at the air bubbles produced by an aquarium aerator. Watch how quickly the bubbles rise to the surface. They provide little aeration, but are aesthetically pleasing to watch. The smaller the bubble, the longer it will remain suspended in the water. And it will rise more slowly, giving it more time to dissolve in the water. Due to the higher density of salt water, air bubbles are usually smaller in salt water than in fresh water. “Small bubbles can theoretically aerate 6.6 times as much water with the same amount of air,” says Ganguly. He gives an example: A large 20 mm bubble has a volume of 4.19 cc, and a surface area of 12.6 cm2. You could make 260 small 3mm bubbles from the large bubble. They would have a total surface area of 83.6 cm2. This is 6.6 times the surface of the 20mm bubble.

What about live wells?

These come in many shapes and sizes. Oval or round tanks provide the best circulation. Rectangular or square wells can work pretty satisfactorily if there is a directional discharge into the well to induce a desirable circular motion.

Good pumps are a must in live wells. Thru-hull pumps provide a constant flow of new water into the live well and eliminate the problems of heat and ammonia build-up. As long as clean water is available, more bait can be placed in a given amount of water than with any of the previously discussed systems. However, when entering water that is less than ideal for delicate bait, care must be taken to secure the intake water. By utilising a combination of the thru-hull pump with other aeration methods, bait can remain healthy and lively for longer periods of time.

Effective aerators:

Venturi Aerators are the best buy. They can be purchased as a floating aerator or a bottom aerator with suction cups. The fast-moving water at the output of the pump creates a vacuum, which sucks air into the pump output. This system typically provides larger amounts of smaller air bubbles.

Spray bar aerators add oxygen to the water by jetting small streams into the surface. Some air is absorbed into the spray as it passes from the spray bar to the water surface, and when the spray strikes the water surface, air bubbles are injected into the water. For the most part, these bubbles are rather large.

Jets of water from spray bars are generally harsh to delicate bait. Their protective coating and scales are easily removed, and their survival is drastically reduced. Hence spray bars are used only on the hardiest bait.

Air stone aerators are inexpensive and useful for small containers. They are quiet and gentle, but because their bubbles are typically larger, they need a greater amount of bubbles for a large amount of bait. These aerators do provide gentle aeration, but they sustain less bait per unit of air than aerators that produce smaller bubbles.