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Transporting and releasing your fingerlings

 

When you are taking your fingerlings home they will be packed in a heavy-duty styrene airfreight box. This is to help keep your fingerlings cool. You should also do everything you can to help to keep them cool.

Do not leave the box in the sun.
Do not leave the box in a parked vehicle in the sun.
Do not place box in a "cool-room" as this will be too cold.
Do not open the bag until you are ready to release the fish.

The fingerlings are packed in a plastic bag containing about ten litres of water, and inflated with pure oxygen. If you open the bag you will loose the pure oxygen, the fish cannot survive long without it. Your fingerlings will survive for up to 48 hours, however when they are packed it is understood that they will be released AS SOON AS YOU RECEIVE THEM. If you do need to have the fingerlings held in the box for longer this should be advised at the time of ordering.

 

Releasing your fish into a Dam

Try to avoid releasing fingerlings in the middle of a hot day. Young fingerlings, in fact most fish, will not be comfortable in bright sunlight. For these reasons you should release your fingerlings very early or late in the day. Late in the day is likely to be when most people will have the opportunity to release their fingerlings. 

Choose a shady spot near deep water. If there is no shade perhaps it is still too early to release your fingerlings. Place the box at the edge of the dam. Carefully open the lid of the box so that you don’t puncture the bag. Using a key is a good way to cut through the tape around the lid of the box. Open the lid slowly letting in just a little light at first. Sudden bright light will frighten the fingerlings and add to their stress. After a couple of minutes remove the rubber band from the bag and slip the bag out of the box allowing the fingerlings and their water to remain in the box. Allow the fingerlings to swim around in the box for about a minute  (no longer) then add a couple of litres from your dam to the box using a jug or similar container. Wait another minute or two and add another couple of litres. Continue this process for about 10 minutes until the box is full. The fingerlings may now be placed in your dam. This is best done by sliding the box into the water and floating the box out over water that is at least 60 centimetres deep. (It is important that the place you choose to release the fingerlings has deep water. This will allow the fingerlings to swim down to cooler water.) Then just tip the box over slowly allowing the fingerlings to swim away.

If the day you intend to release your fingerlings is overcast and not too hot, you may find the above process will not be required. Temperature is the main reason for slowly mixing water. If you feel the temperature on the surface of your dam is the same or very close to the temperature of the water the fingerlings are packed in, then you may simply release the fingerlings directly from their bag into your dam. Another reason for the above mixing process is, when the fingerlings have been held in their bag for an extended length of time. This causes the level of carbon dioxide to build up in the packing water. In the presence of high oxygen the fingerlings can survive the high concentration of carbon dioxide, but they may go into shock if they are added too quickly to water that has normal levels of oxygen. Therefore the mixing process should be followed whenever fish have been held in bags more than 6 hours.

 

Releasing your fish into a tank

Carefully open the lid of the box so that you don’t puncture the bag. Using a key is a good way to cut through the tape around the lid of the box. Open the lid slowly letting in just a little light at first. Sudden bright light will frighten the fingerlings and add to their stress. After a couple of minutes remove the rubber band from the bag and slip the bag out of the box allowing the fingerlings and their water to remain in the box. If available, place an air stone into the box as this will aid in recovery and it is recommended that an air stone is put into the box.. Allow the fingerlings to swim around in the box for about a minute  (no longer) then add a couple of litres from your tank into the box using a jug or similar container. Wait another minute or two and add another couple of litres. Continue this process for about 10 minutes until the box is full. Once the box is fulled, place a small number of fish into the destination tank. Observe these fish for several minutes. If these fish are alright and swimming normally after several minutes, add the remaining fish. Do not feed the fish until the following day.

Temperature is the main reason for slowly mixing water. Another reason for the above mixing process is, when the fingerlings have been held in their bag for an extended length of time. This causes the level of carbon dioxide to build up in the packing water. In the presence of high oxygen the fingerlings can survive the high concentration of carbon dioxide, but they may go into shock if they are added too quickly to water that has normal levels of oxygen. Therefore the mixing process should be followed whenever fish have been held in bags more than 6 hours.

 

Fingerling growth*

It is difficult to say just how fast your fingerlings will grow. Each dam contains a different amount of natural food. Even the water quality of the dam has an effect on the growth rate of fingerlings. However as a general guide you can probably expect that Silver Perch will grow faster than Australian Bass. Silver Perch, if not fed, will under reasonably average conditions, reach about one kilo in two years. If they are fed this will rapidly increase their growth rate, allowing them to reach a similar size in about half the time. Remember Bass cannot be expected to take artificial food. If you feed your fish store the food in a cool, dark, dry environment to retain the full nutritional value of the food.

 

Perch fingerlings have been feed at Ausyfish with “Barramundi dust”. This is a high protein food best for small fish. As the fish grow, larger sized food should be used. Once the fish are around 15 centimetres “native fish diet” may be used. This is a cheaper food than the higher protein Barramundi food.  To purchase high quality aquaculture food contact Grobest Australia on 1800 005 434. 

*You can not sell your fish. It is illegal to grow fish for sale without proper authority. Contact the fisheries or aquaculture section of your local authority.