When choosing the fish to use in your aquaponics system, you’ll need to look at the factors that will affect this decision. Many fish will work in an aquaponics system, but you’ll need to be the one to decide which fish will work for you. If you are looking for fish that does the best in this system, you’ll need to decide if you plan on harvesting the fish once they've reached maturity. If you don’t plan on eating the fish that you’re raising, you won’t need a tank that is larger than a normal tank. You’ll also only need fish that you can purchase from your local pet store, instead of fish that you’ll need to buy from a fish supplier.
If you plan on using a fish that you’ll be able to eat, one of the best options is tilapia. This fish has been proven to do the best in an aquaponics system for many reasons. Tilapia fish are able to adapt really well to changes that occur in the water. With an aquaponics system, your water will change frequently since you’re funneling water from the tank to your plants and then back again. Tilapia are also really easy to purchase while young. The only disadvantage of tilapia is that you may not be able to grow tilapia in your state. Some laws regulate the raising of fish so you should make sure that you’re familiar with the law before making a choice.
If you don’t want to use tilapia, many other food fish do well in an aquaponics system. You can use catfish, salmon, trout, or bass. With catfish, you may run into a problem of getting the fingerlings. Catfish fingerlings are typically only available three months out of the year. Since you’d need to purchase your fingerlings then, you may have to deal with a problem of replacing the fish once you've harvested them. With salmon or trout, you’ll need to be raising your fish in a colder climate. These fish may be more costly to raise since you’ll need a system that heats and cools the water.
If you don’t plan on eating your fish, you can use Koi or goldfish. Both of these fish will do well in an aquaponics system that isn't being used to harvest fish. Koi tend to produce a lot of waste so they make a great choice for this type of system. You may even be able to sell some of the Koi that you've raised. Goldfish do well in aquaponics systems but they may present a problem. How do you get rid of them? Some goldfish will reproduce too much so they may need to be removed from your system.
Choosing the best fish for aquaponics isn't a decision that you should take lightly. You should look at your uses for the fish, the space that you have, and how easy you’ll be able to obtain these fish. If you make a choice of fish from the fish that are known to do well, you’ll see a wonderful garden unfold before your eyes.