Your new fish should be kept in a separate, isolation tank for at least 2 weeks. If you do not have a separate isolation tank, any other large container that is free of chemicals may be used. Make sure that you put a heater and aeration in the temporary tank. Remember, this is only temporary. After two weeks, When the fish are showing no signs of stress or disease, they can be moved to their permanent aquarium. CHANGE 40% OF THE WATER DAILY FOR THE FIRST WEEK AND THEN EVERY OTHER DAY FOR THE SECOND WEEK.
It is urgent that you unpack your fish as soon as possible. Float the container in the isolation aquarium where they are going to stay. DO NOT open the container at this time! You may find that you need to remove some of the aquarium water to prevent it from overflowing when the containers are placed in the aquarium. If necessary, remove some aquarium water into a clean plastic bucket or other food safe receptacle. Be sure the container for excess water does not have any reside from household cleaners or other potentially toxic chemicals, as you will use this water to refill the aquarium later.
Allow the containers to float for 30 to 40 minutes to allow temperatures to slowly equalize (longer if necessary). Open the fish containers only when you are ready to immediately put them into your aquarium. DO NOT put any water from your aquariums into the containers or vice-versa! Avoid netting as much as possible. Gently pour off most of the water from the container thru a net. Then release the fish from the container directly into the aquarium. Another good method uses a smooth plastic spaghetti strainer with small holes. Gently scoop or release the fish into the receptacle, drain the water and place the fish immediately into the aquarium. Large specimens can often be simply hand placed into the aquarium. If these methods are not applicable, place a large net over the top of a clean bucket with enough water to cover approximately a third of the bottom of the net. Open the bag and carefully pour some of the fish into the net and immediately place them directly into the aquarium. Try to avoid a net full of fish as they will ball up in the net, and the ones underneath can be damaged from compression and friction. Remember that water from the container may react with the water from the aquarium, and could be very harmful. Never mix container and aquarium water!
Sometimes during shipping, fish lie at the bottom of the container and appear dead. “Playing opossum” is a common animal stress behavior. Carbon dioxide also acts to tranquilize the fish. Even if the fish look like they are mostly dead, put them into an aquarium as outlined above. Leave the aquarium lights off to further reduce stress, and leave them alone. You will be amazed how clean water and stress reduction help!
Like other animals, fish produce carbon dioxide as they breathe. When carbon dioxide is dissolved in water, an acid is formed, lowering the pH of the water just like in a carbonated beverage. Fish also produce ammonia, which can be very damaging. Ammonia is present in water as NH3 or as NH4+, or as a combination of these forms. The toxic form of ammonia is NH3. The proportion of NH3 versus NH4+ is dependent on pH. The lower the pH, the lower the amount of NH3, and the greater the proportion of the less damaging NH4+. In the wild, freshwater fish naturally experience wide changes in pH.
One of the reasons fish are able to be shipped long distances in closed containers is because the pH in the shipping water drops, making the ammonia non-toxic. The carbon dioxide acts as a tranquilizer. The moment the container is opened, and exposed to the outside air, carbon dioxide escapes, the pH of the water immediately begins to rise, and ammonia becomes deadly. Fish tissue damage will then occur very quickly. NEVER add water from a shipping container into your aquarium, as you do not want all that harmful ammonia in your aquarium. NEVER add water from your aquarium into the shipping container. Acclimate the temperature by floating the container in the aquarium water, and then immediately open the container and release the fish into the aquarium, minimizing the introduction of the container water.
****VERY IMPORTANT*** ***PLEASE BE PATIENT**** YOUR DISCUS WILL NOT SHOW THEIR FULL COLORATION FOR SEVERAL DAYS !! THEY WILL START TO GET THEIR COLORATION IN A FEW DAYS AND SHOULD HAVE THE FULL COLORATION FOR THEIR AGE WITHIN ONE MONTH. MOST DISCUS DO NOT SHOW THEIR FULL AND FINAL COLORATION AS JUVENILES AND WILL NOT UNTIL THEY ARE MATURE ADULTS (AROUND 5"). DISCUS WILL OFTEN LAY ON THEIR SIDES FOR A FEW HOURS, OR EVEN SOMETIMES A COUPLE OF DAYS, AFTER THE STRESS OF SHIPPING. CHECK THEIR GILLS FOR AT LEAST 5 MINUTES TO MAKE SURE THEY ARE NOT BREATHING BEFORE GIVING UP ON THEM! DO NOT FEED YOUR DISCUS FOR 24 HOURS AFTER YOU RECEIVE THEM. DO NOT PUT ANY BRIGHT LIGHTS ON THEM FOR THE FIRST DAY.