Unpacking and Releasing your New Fish

Transporting and releasing your fingerlings.

Unpacking and Releasing your New Fish


Non commercial densities means, your fish are lightly packed. They will have much cleaner water than fish packed at high density for commercial customers. Usually this means there are about 103 fish per box. (We pack an extra 3 fish in each box for non commercial customers.) When you are taking your fingerlings home they will be packed in a heavy-duty polystyrene 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.) Don’t open the bag until you are at the dam or tank where they are to be released. The fingerlings are packed in plastic bags containing about ten litres of medicated water, and inflated with pure oxygen. If you open the bag you will loose the pure oxygen, the fish cannot survive long without it. In  fact without the pure oxygen they will only last a few minutes. Your fingerlings will survive for up to 48 hours, however when they are packed it is understood that they will be released the day they arrive. If you do need to have the fingerlings held in the box for longer, tell us when you order them so we can pack them to survive longer. This is easy. We can pack your fish to last for as many days as necessary.


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 over 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. 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. Add about 3 litres of water from your dam. be sure to take cool water. On a hot day the surface water may be very warm, and unsuitable for the fish. Allow the fingerlings to swim around in the box for a minute or two, then add another couple of litres from your dam to the box. Use a jug or similar container. Wait another minute or two and add another couple of litres. Continue this process for the next 10-15 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 centimeters deep. Then just tip the box over slowly allowing the fingerlings to swim away. It is a real advantage if you have a battery operated air pump, like the ones used to keep live bait for fishing, use the pump in the box during this acclimation process.

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, causing 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 12 hours. For more about carbon dioxide read the information on how to unpack a commercial quantity of fish.


This process is much the same as the above dam release method. The differences are, you don’t need to worry about warm water near the surface, therefor the time of day is not relevant. If you have an air stone available to bubble the water in the box while acclimating the fish, (Adding your tank water to the shipping water.) this would be a real advantage. Follow the same process above by releasing the fish into the box and adding water from you aquaponic tank, then tip the fish out of the box into your tank.


Commercial packing densities are usually five times greater than non commercial customers. Commercial customers MUST follow our unpacking procedure if they are to achieve the best survival. We pack at such high densities to better manage the freight and packing costs. On arrival, your fish will appear groggy and appear to be struggling for survival. DON’T panic ! It is normal for them to look this way. Follow the commercial unpacking procedure, and they will survive. If you don’t follow the procedure, you WILL lose large numbers of fish !

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 Aussie Fish Aquatics 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.