There are a number of theories when it comes to receiving a shipment of fish. I will explain my methods for receiving a shipment from the preparation of the tanks to feeding in the following days after the shipment.
First, let us start with preparing the tank. I do approximately 20% water changes on the tanks that are going to receive the fish the night before the shipment arrives. I also try to keep some fish in the tank until the night before to keep the biological filtration working well. One of the most important things for receiving fish is well-established biological filtration. I personally use sponge filters in all of my tanks to accomplish this. It is important for the pH to be stable. pH fluctuation can be a great shock to a fish that has just been shipped. I personally use carbonate-based sand to accomplish the necessary buffering. I personally check each tank to make sure that all the tank conditions are correct the night before I receive the fish.
Now let’s move on to receiving the fish. It is important to get to the airport as quickly as possible to pick up your fish. Air Cargo people have been known to forget fish boxes outside in the heat or cold. Make sure you know the hours of operation for your local office. Most of the time if a shipment is going to arrive outside of these hours arrangements can be made to ensure that you can pick up your fish. It is important to treat the Air Cargo representatives well as they can be the difference between the life and death of your fish. Once you get your fish back to your house make sure that the temperature of your tanks is still good and try to keep the lighting dimmed if possible. Once you have checked on your tanks it is the time you have been waiting for opening up your boxes and seeing your new fish. Take one bag of fish out of the box check for DOAs and then cut the bag and net the fish out and put them directly in their new home. Avoid handling the fish as much as possible and try to keep any water from the bag from getting into the tank. Make sure to only open one bag at a time because once exposed to fresh air ammonia builds up quickly. Your fish are going to be carrying quite a bit of ammonia into the aquarium and that is the reason for the importance of a good biological filter. Once you have gotten everyone into their new tanks take a look and make sure everyone is alive and well. It is important to remove any dead fish as quickly as possible to avoid any additional ammonia buildup.
Now that your fish are starting to settle in it is important not to stress them out anymore than necessary. I personally don’t feed any of my new fish until they have been in their new tanks for at least 12 hours depending on how they are doing at that point in time. The initial feeding should be very light to see how they respond. Feedings should gradually be increased until they are at a normal level. Sometimes fish lose a substantial amount of weight during the entire shipping procedure. I try to increase feedings beyond my normal one-time-a-day feeding schedule for fish that come in skinny. Once your fish get comfortable in their new environment you can try to turn on the light. They will probably not like it at first and so you need to make sure that the fish have settled in well before attempting to turn on the light.
If you follow these steps you should have happy healthy fish that recover quickly from the stress of shipping.