It’s important to add fish gently to a freshwater tank. The key is to proceed slowly so the new inhabitants have a chance to properly acclimate to their new surroundings. One of the most common mistakes new hobbyists make is just pouring the fish into the tank. This is not a good idea because fish can become stressed by sudden shifts in water temperature. The same goes for any inhabitants in a tank including freshwater shrimp and freshwater snails.
Fish are cold blooded animals. Their body temperature is directly related to the temperature of the water in which they swim. So its a good idea to float the bag in aquarium water for at least 20 minutes before adding fish to the tank. Floating the bag in tank water gives the water temperature inside the bag a chance to equalize with the water temperature in the aquarium. If the water temperature in the plastic bag feels like it really does not match the tank water, let the plastic bag float in the tank water for longer than 20 minutes. After another 10 minutes or so, the water temperatures should feel more like the match to the touch.
Add Fish Gently – It’s Key To The Process
Once the water temperature seems balanced, adding fish gently to the tank is the next step. Its a good idea to add as little of the bag water into the tank as possible. Carefully pour some of the bag water into a bucket. Make sure the fish remains in the bag. Also be careful not to hurt the fish. Its important to leave enough water in the bag so the fish doesn’t get injured. Then place the bag in the aquarium. Submerge the opening so tank water fills the bag. Tap the outside of the bag gently to encourage the fish to swim from the bag to the tank on its own. Be careful not to pour the fish into the tank. The fish have been through enough stress during transport. The last thing fish need is to be “poured from a bag” at the end of their journey from the store.