Spring and fall are the best seasons for stocking fish in your new pond. In these months, oxygen levels are high and temperatures are mild. This ensures that any stress factors that may affect your fish will be at their lowest. You can also add fish to your pond in the summer, but keep in mind that they will require a little more time to adjust in this instance.
When you first stock your pond, you should add some fathead minnows to feed any predator fish so that your prey fish have a moment to get established. In ideal conditions, minnows can be snacks for your other fish that will replenish themselves.
Acclimating your new fish is simple. First, place their transportation bag in a shaded area of your pond. Let the bag float for approximately 20 minutes. This will allow your fish to gradually adjust to the water temperatures in your pond.
Now you can safely open the bag and let your fish swim out into the pond on their own. If you are adding new fish into a pond where there are already other types of fish, you will want to release them in separate areas. For instance, you can release minnows at one end of your pond to attract your larger fish while releasing smaller fish at the opposite end to ensure that they have a chance to secure shelter. When your pond is properly stocked, your fish population will keep itself in check.