By Kenneth Williams

 After pond construction or renovation is complete; the pond is ready to be stocked with fish. Fingerlings (fish smaller than 6-8 inches) are commonly sold for this purpose. However, stock grass carp or channel catfish fingerlings at least 7 -10 inches in length if largemouth bass are already established in the pond. Large quantities of fish may be delivered directly to the pond in a commercial hauling truck (Consult fish broker to determine transportation or pick-up method.). Smaller amounts may be delivered to a local cooperating agricultural business and picked up at a specified time by the pond owner; or the pond owner may choose to haul the fish directly from the producer to the pond. In each case the fish must be carefully transported and acclimated to the new pond environment.

Commercially delivered fish
Depending on size of fish and price, fish may be delivered directly to the pond if road access is available. Be prepared for the new arrivals. Plan to be at the pond during the time the fish are stocked. Have a thermometer available to measure water temperature. Know before delivery whether the fish hauler will be able to “temper” the fish. This is most conveniently done by pumping water from the pond slowly into the hauling tank until the tank water is brought to the temperature of the pond water. This should be done over at least a 30 minute time period to avoid shocking the fish from abrupt temperature, pH or other water quality changes. At minimum, temper water 20 minutes for each 10o F difference in water temperature. If temperature differences between pond and hauling tank are not gradually brought into equilibrium, many of the fish will die in the first week or two after stocking. Bluegill, largemouth bass and hybrid striped bass are particularly sensitive to temperature shock. In addition, hybrid striped bass are very light sensitive, especially if they are larger than about 6 inches. These fish are best stocked at dawn or dusk if possible. If not keep them shaded or covered until they are released into the pond.

Should the fish hauler be unable to temper the fish, have several tubs available for this purpose near the pond. Place the fish into the tubs with water from the fish hauling tank. Slowly replace and dilute the hauling tank water with pond water as described above. Place the fish into the pond when water temperatures in the tubs and the pond are the same.

Dissolved oxygen depletion can become a problem if fish are removed from the hauling truck for “tempering”. Fish should remain near the bottom of tempering containers. Fish rising to the surface and “piping” or “gilling” rapidly may be running out of oxygen or toxic levels of ammonia may be present. In either case aerate the water. Use of inexpensive battery powered bait bucket aerators can help maintain dissolved oxygen levels in the water. In emergency situations where aerators are not available, aerate the water by repeatedly filling a bucket with the tub water and pouring it back into the tub from a height of 1-2 feet. Allowing the water to splash over a board or other object as it falls will further break up the water and increase aeration. This method of aeration should be used in emergencies only as it can frighten or harm fish. Hybrid striped bass may go into shock and die from this treatment. Fish larger than about 6 inches may injure themselves by hitting the sides of the container or jumping out of it.

Receiving bagged fish
Fish are often delivered to a central location by the fish broker on a specified date and time. Fish will be placed into plastic bags filled about half full of water. The bag then will be inflated with oxygen and ready for delivery. The pond owner should place the bags in covered, insulated coolers for the return home to prevent water heating and to reduce the possibility of light shock.
Temper fish by floating bags directly in the pond in a shaded location. Water temperature in the bags should be about the same temperature as the pond in about 30 minutes. At this time begin replacing and adding pond water to the bags. Watch fish for signs of oxygen depletion and aerate water in the bags if necessary.

Release the fish in an area of the pond that is shaded and has abundant aquatic vegetation. The fish may be stressed and disoriented when released. Vegetative cover reduces stress which improves survival success. This is very important in ponds that already contain fish because it reduces the chance of predation while the fish is recovering from transport and adapting to the new pond. Grass carp and channel catfish are often stocked into ponds already containing established fish populations. Largemouth bass may consume many or most of these fish if they are not released into areas protected by vegetation. Better protection can be provided by screening off a small area of the pond with 1/8 -1/4 inch plastic or wire mesh. Release new fish into this area for 1-2 weeks. This allows the fish to become adapted to the new environment without facing the perils of predation. It also allows the pond owner to observe any fish loss due to transport and stocking.

Hauling fish from the producer
The pond owner may elect to haul fish from the producer to the pond. The producer may provide the fish in oxygenated bags as described above in which case the procedure is the same. The pond owner may decide to haul the fish in barrels of water if oxygenated bags are not available. The pond owner must be prepared to safely transport fish. Plastic or metal barrels with lids are often used. Securely fasten barrels to the bed of the truck, behind the cab for added support. Battery powered bait aerators can be purchased inexpensively and can help keep hauling water oxygenated during the trip to the pond.

You will also need a couple of 5 gallon plastic buckets and a dip net for transferring or aerating water; and to transfer fish to the pond.

Quickly transfer fish from producer holding tanks to the hauling barrels. Avoid exposure of fish to sun and wind.

Water treatment
Plan to have at minimum, 1gallon of water for each 0.1 lb of fish if hauling fish smaller than 6 inches in length. Larger fish can do with somewhat less water. Water needs are greatly reduced if oxygen aeration is available, however this equipment is beyond the needs of most pond owners.

Lower and maintain hauling water temperature at about 60oF if the trip is more than an hour. Hauling temperature should be about that of the pond water for short trips. Use de-chlorinated ice if possible or leave chlorinated ice sealed in bags. Ice added at a rate of 0.5 lb/gallon of water will lower hauling tank temperature about 10oF. Colder water holds more oxygen than warmer water. Also Cool water reduces stress on fish by lowering their metabolic rate which reduces the amount of ammonia fish release into the water; and less of the released ammonia is in a toxic form.

The fish will travel best if placed in a 0.03 % solution of table salt made by mixing 6 tablespoons of salt per 10 gallons of water. Salt reduces osmotic stress on the fish making it easier for the fish to retain metabolites and excrete waste products from the gills.

Hauling fish
Proceed directly to the pond after loading the fish. Do not stop to run errands or other activities. Fish will do best if kept in the hauling tanks the least amount of time possible. Drive cautiously. Brake and turn smoothly to avoid water loss. Sloshing water often can turn barrels over resulting in damaged or lost fish. Lids shade the fish and prevent water and fish loss. Long hauling times and large quantities of fish require methods best left to commercial fish haulers; however, the size and quantity of fish stocked in most ponds can be hauled easily in the back of a pickup truck.

On arrival
Temper the fish in the barrels on arrival at the pond. Raise water temperature in barrels to that of the pond by slowly adding pond water to the barrels over 30-45 minute time period. At minimum, temper water 20 minutes for each 10o F difference in water temperature. Aerate the water frequently if fish begin to rise to the surface. Transfer fish to the pond in plastic buckets.

It must be assumed that all incoming water of unknown origin is infected with koi herpes virus (KHV), viral hemorrhagic septicemia virus (VHSv), zebra mussels or other harmful organisms. Do not pour this water into the pond. Transfer the fish in nets or buckets of water from your home pond. Treat the hauling water with chlorine bleach before dumping it.

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