Choosing the best fish for aquaponics systems is a challenge. There are many factors that we will have to consider before deciding what aquaponic fish is best for you. The biggest questions that need to be answered are, “Do I have enough space in my aquaponics fish tank”? The other big question is, “Do I plan on consuming the fish from my fish tank garden”? This article will cover some of the best freshwater fish that are suitable for your aquaponic system depending on space, size and desire to consume the animal.
Best Fish For Small Aquaponics Systems
There are hundreds of different species of freshwater fish available for purchase at pet stores. You can find aquarium fish for sale in person and/or online. The challenge is choosing the right one for you and your system. We will be looking for low maintenance fish that can tolerate water conditions that may not be ideal. We will be discussing some of the best freshwater fish for aquaponic systems that don’t plan on being consumed.
Guppies and Endlers Livebearers
The first fish we will talk about will not be grown for food. Guppies and Endler’s Livebearers are fantastic fish for smaller aquaponic systems that you may have indoors. They stay small, readily reproduce and are fairly hardy. This species of fish will require certain parameters to keep them happy in aquaponic systems.
- Temperature Range: 74 to 82°F (23-28°C)
- pH Range: 7 to 8
More than likely, you will need a heater keeping this fish species warm. A Fluval M100 Submersible Heater, 100-Watt Heater might be a perfect choice depending on the size and dimensions of the aquaponics fish tank. If you have male and female guppies in your fish tank, they will easily breed with one another to repopulate the system.
Tetra Fish
There are hundreds of different species of tetras out on the market. Just like the guppies, you can find tetras for sale online and in most pet stores. Choosing the best tetra species for an aquaponic system might be overwhelming. I cannot go over each species but I will name a few that are very hardy and others that may be less so. Just like the guppies, this fish species will be used in an indoor aquaponics system and will need both heating and specific water parameters to keep them happy. These Tetra species are also going to be inedible. They will be more for display and waste producing purposes only. They will require the following for success:
- Temperature Range: 73 to 78°F (22-25°C)
- pH Range: 6.7 to 8.6
Each tetra species will have specific requirements, so you will need to read up on the species that interests you. There are a few excellent tetras for beginners that should work in an aquaponics system. They are:
- Serpae Tetra
- White Skirt Tetra
- Black Skirt Tetra
- Red Eye Tetra
- Pristella Tetra
These fish should be more tolerant of changing water parameters. Unfortunately, they are not as vibrant and colorful as some of the other species. If you are looking for tetra fish that are less hardy but cool fish because of their more vibrant colorations, check out the following:
Fish like Neon Tetras and especially Cardinal Tetras are more prone to having adverse effects to fluctuating water conditions. Make sure you fine tune your aquaponic system before you introduce these species.
Best Fish for Large Aquaponics Systems
This next section will discuss freshwater aquaponics fish that will require larger fish tanks. I will make note of the minimum fish tank size for each but with these fish, larger fish tanks are better. Also, not all of these fish species will be edible but are excellent candidates for an aquaponics garden.
Goldfish
Goldfish are an amazing choice for an aquaponic system because they do a few things. First, they do not have a stomach so they produce a lot of waste which is great fertilizer for your plants. Second, they are a cooler species of freshwater fish so are more tolerable in room temperature water. This my cut a heater out of the equation when setting up an aquaponics system. Lastly, depending on the species they can be incredibly cheap. Feeder goldfish are only a few cents at fish store. Even more exotic goldfish such as Oranda or Ryukin Goldfish aren’t too expensive. You can find goldfish for sale almost anywhere. Goldfish will require a few things:
- Minimum Tank Size: 30 Gallons (larger is better though)
- Temperature Range: 65-75° F
- pH Range: 6.5-7.5
The more water that a goldfish has the more stable its water parameters will be. Goldfish are technically edible but I personally would not recommend eating them. If you are looking for fish to eat, check out the next set of fish.
Tilapia
The Tilapia is an excellent fish species for your fish tank garden. They are fairly hardy, eat many different foods, and are edible! Overall, for a fish the Tilapia grows fairly quickly. They should be ready for harvest after about half a year. It is recommended to have them weigh around a 1 pound or more. The amount of Tilapia you keep will be determined by the size of the fish tank and also size of the garden. If you have too much fish and not enough plants, the water parameters will go out of whack which may cause your fish to become diseased. Finding the right balance between number of Tilapia and size of garden/aquarium is key. I would make sure the fish tank for Tilapia is not smaller than 125 gallons. In a tank this size, you should be able to keep between 20 and 30. The following are requirements for your Tilapia:
- Temperature Range: 70-85° F
- pH Range: 6-9
- Extra Aeration
Tilapia will more than likely need a large heater in their fish tank to keep the temperature at the proper level. They will probably need a form of addition aeration because warmer water does not hold as much oxygen. Otherwise, Tilapia are incredibly hardy and breed very easily. It should do well in a well setup aquaponic system. I have not seen Tilapia for sale at fish store but you should be able to find them online.
Bluegill
Native to North America, the Bluegill is often used for Aquaponic systems. Overall, they are a smaller fish and max at about 16 inches in length. You will see them more commonly at about 8 inches in length. They’re fairly hardy fish and will eat different algae and vegetation that may grow in the aquaponics system. I personally would not keep them in anything smaller than a 75 gallon fish tank but larger is always better. They do best with the following water parameters:
Temperature Range: 70-75° F
pH Range: 6.5-8.5
The temperature window for Bluegill is not incredibly wide. Having a larger heater in the aquarium will help keep water temperatures stable and within range. This fish species is not commonly sold at pet stores but you can find Bluegill for sale online. Lastly, many skilled fisherman will harvest live Bluegill from local waterways and add them to their aquaponics system.
Final Notes
There are many fish and invertebrates that can be added into an aquaponic garden. These are some of the best fish for aquaponics systems. If you are setting up an aquaponic system, check out the differences between vertical and horizontal systems and decide which is the best size for you! Whether you choose Tilapia, Bluegill or small tetras, your aquaponic system could be very successful if done correctly!