Good Livewell Management
August 10, 2006
It can be the tournament angler’s worst nightmare – opening his livewell at the weigh-in only to discover that his prize winning fish have died. Not only has he needlessly killed his magnificent quarry but the subsequent point penalties have probably dashed any dream he had of winning the tournament. Good livewell management can indeed be the difference between winning a tournament and finishing well down the leader board.
Before we discuss the elements of good livewell management, let’s try to understand why it is important. First, consider what your prized catch must endure in order to survive during a tournament day. He is yanked from his comfortable surroundings, muscled through the water to the side of the boat, hoisted in the air by a net or the excited grip of an angler, jostled as the hook is removed, laid horizontally on a dry aluminum measuring board, and finally dumped into a dark, strange ‘holding tank.’
Add to these life-threatening experiences the prospect of having to remain in that foreign environment for many hours prior to the day’s weigh-in. The stress levels for those red bruisers will be off the charts. It’s no wonder that some die in the process. Yet with good livewell management, the chances for survival are outstanding.
Actually all that is necessary for a redfish to survive and even flourish in your livewell is providing and maintaining adequate levels of oxygen while avoiding dangerous levels of carbon dioxide, ammonia and metabolic wastes. Let’s address how to develope sound strategies for these critical elements.
Oxygen and Carbon Dioxide
Sufficient oxygen levels are the single greatest concern in good livewell management, and there are a variety of issues involved in maintaining them. Most livewells come equipped with some sort of an aeration system designed to replenish the depleting oxygen while removing increasing levels of carbon dioxide which may prove deadly to your catch if left unattended.
By far the most common are ‘fresh’ water systems, which pump new water into the livewell while the old water drains out. This system uses thru-hull pumps to provide a constant flow of new water and may prove adequate in many situations for the tournament angler. However, it should be noted, fresh water systems will only be as effective as the water surrounding the boat.
If the ‘fresh’ water being pumped into the tank exceeds 80 degrees, it will add very little new oxygen to the livewell environment. Moreover, in areas where the water is somehow tainted, toxic or oxygen depleted, introducing ‘fresh water’ into the livewell would be dangerous to your prized catch.
Aeration systems that provide recirculation where the environment within the live well can be controlled and protected often prove to be very efficient at maintaining the health of your redfish. Recirculation systems that feature micro-bubbles give the tournament angler the best of all combinations. It is a fact: the smaller the bubbles the more efficient the exchange of oxygen into the water and carbon dioxide from the water.
Types of Recirculation Aerators: There are three different varieties of recirculation systems: spray bars, air stones and Venturi aerators. Spray bar aerators add oxygen by jetting small streams of water into the surface of the water within the livewell. This system will add some oxygen to the water in the livewell, but not much. Furthermore, the violent jetting process can cause the redfish to lose scales and become further stressed. This is not an efficient system.
Air stone aerators are another popular type of oxygenation. Since air stones gently force air into the water below the surface there will be significant oxygen/carbon dioxide exchanges. However, the bubbles produced by most air stones are generally large, and thus they are not the most efficient means of oxygenation either.
Ironically, in this age of constant technological improvements, the old Venturi aeration systems remain hard to beat. This inexpensive pump system can be purchased as a floating or bottom aerator with suction cups. The fast moving water at the outflow of the pump creates a vacuum which sucks air into the output of the pump producing large amounts of smaller bubbles – a very efficient oxygenation system.
Pure Oxygen Systems: Another strategy to add oxygen into the livewell system involves the infusion of pure oxygen to the water. On the surface, this would seem to be the best possible scenario; after all, fish need oxygen to survive. However, there are several problems associated with pure oxygen systems. Unless the system is installed properly, you may find that it will not provide an adequate means for removing carbon dioxide from the water. Too much carbon dioxide is toxic to fish and too much pure oxygen can prove fatal to the fish. Hence, when using pure oxygen systems, oxygen levels require close monitoring.
Water Temperature
One of the simplest and most important aspects of good livewell management concerns water temperature. The warmer the water, the less oxygen it will hold and fish deplete the oxygen quicker as the water warms. As a rule of thumb, lowering the temperature of the water in your livewell by 20 degrees will add as much as 25% more oxygen to the water.
Livewell water can be cooled by using frozen ‘jugs’ of water or dumping ice directly into the tank. Three notes of caution on chilling your water: 1.) Care must be taken not to lower or raise the temperature of the water too quickly which would shock the fish. 2.) Monitor the sudden loss of salinity if water is cooled through the dumping of ice into the livewell or risk damaging the cell structure of the fish. 3.) Remove frozen ‘jugs’ while traveling to avoid bruising your beauties.
Ammonia and Metabolic Wastes
The other factor in livewell management that needs attention is levels of ammonia and metabolic wastes - toxic substances introduced into the livewell by the fish themselves. Many times, simply replacing the water in the livewell will take care of this issue, and a good rule of thumb would be to replace the livewell water every four hours. (Warning: if you have significantly ‘chilled’ the old water, you must be very careful not to suddenly reintroduce your fish to fresh water with substantially higher temperatures.)
Chemical Additives: There are several chemical additives employed by some tournament anglers as a means of creating a stable environment for redfish within the livewell. These include Hydrogen Peroxide, Redfish Saver, Rejuvenade and Voodoo Dust.
Some marine biologists suggest adding 3% Hydrogen Peroxide to your livewell environment to help optimize healthy conditions (1 oz. of 3% Hydrogen Peroxide to 4 gallons of water). Hydrogen Peroxide helps remove ammonia and metabolic wastes from livewell water and even neutralizes the effects of any chlorine that may have been introduced by dumping ice into the tank.
Redfish Saver, distributed by Sure-Life Laboratories, Inc., and Voodoo Dust, produced by Audubon Aquarium of the Americas, available at any IFA tournament, are commercial products which also claim to neutralize the harmful elements within a livewell system.
The most popular chemical additive is Rejuvenade, produced by BassMedics. According to the BassMedics website, Rejuvenade “revitalizes, replenishes and re-energizes fish preparing them for release.” The tournament anglers who use these products often swear by them.
With some solid preparation before hand and a little care and attention to the environment within your livewell during the tournament, you can keep your burnished bronze catch kicking and screaming all the way through the big dance at the end of the day.
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