Fish is the most important component in aquaponics. There are many types of fish used for Aquaponics. We have listed the most widely used and suitable aquaponic fish types. You can choose the fish breeds based on their pros and cons, your climatic conditions and other requirements.
The guide gives complete information about most common varieties, including sturgeon, that will work well for aquaponics. This expands well beyond the aquaponics typical focus on tilapia.
In this article, You will be able to choose the best fish suited to your needs. We have mentioned, temperature tolerance, breeding habits, growth & stocking rates, and diet of each fish. You will be able to screen fish for your climatic and space conditions.
The Best Fish Options for Your Aquaponics System
|Name||Vital Temp||Best Temperature||Diet||Culture Environment & Scale|
|Nile Tilapia||1436 °C||Warm (27-30 °C)||Omnivore||Suitable for small-scale Aquaponics|
|Goldfish||13-26 °C||Cool (20-22 °C)||Herbivore||Best for small-scale Aquaponics|
|Koi||0335 °C||Cool (20-25 °C)||Omnivore||Better in outdoor pond|
|Channel Catfish||0534 °C||Warm (24-30 °C)||Omnivore||Tank of atleast 250 gallons|
|Rainbow Trout||10-18 °C||Cold (14-16 °C)||Carnivore||Better in ponds or large tanks|
|Jade Perch||13-32 °C||18-27 °C||Omnivore||Suitable to raise in tank|
|Largemouth Bass||10-36 °C||Warm (24-30 °C)||Carnivore||Ponds or Large tanks of 1200 gallons|
|Murray Cod||10-25 °C||Cool (24-25 °C)||Carnivore||Only suited for tanks at high density|
|Bluegill||13-35 °C||18-27 °C||Carnivore||Good for small-scale Aquaponics|
|Sturgeon||10-30 °C||Cool (18-26 °C)||Omnivore||Better in large pond|
- Edible and are well palatable.
- Warm water fish: 2730°C (80-86°F)
- Vital temperature range: 60-95°F (15-35°C)
- Suitable for tank, cage and pond culture
- Easy to breed in the tank (every 4-6 weeks)
- Omnivores: requires only 22-35% Protein
- Faster growth (600 grams in 6–8 months)
- Highly resilient: tolerates pH shifts, temp changes, high ammonia & low DO
Their rapid breed habits can spread juvenile in the whole recirculation system. In the breeding mode, the males get aggressive and the females stop eating. In cold climates and winter, they may require a fish tank heater to maintain the water temperature. Tilapia is declared as a pest/invader and banned in many areas, so check legality with your state fishery department. In some areas, multiple licenses and regulations on raising and selling tilapia, coupled with its saturated market, Aquaponic farmers find them useless to raise unless they plan to sell fry commercially. You will find good alternatives in this list if tilapia does not suit you.
If you have chosen to stock tilapia, a few channel catfish can make a great companion. These peaceful tank-mates will eat any leftover feed that sinks to the bottom. It will minimize the level of decomposing solids in your tank and save the system from ammonia/nitrite poisoning.
Ask your supplier for a variety that suits your climate. Read more information about Tilapia Aquaponics here.
- Ornamental non-edible fish
- Species of carp
- Cool Water Fish: 22-23°C (72-74°F)
- Requires only 22-35% Protein
- Need plant cover to breed in the tank
- Grow to a max length of 14 inches (35 cm) and 4.4 pounds (2.3 kg) in weight
- Great for beginners because of the cheaper price and easy to keep
If you don’t have a lot of space for the aquaponics system and not necessarily keen on eating the fish, goldfish is a great option. Goldfish are great at tolerating temperature swings to both the high or low end of the temperature range. They can tolerate temp range of 13-26°C. You may not require much heating to maintain the temperature. They are also considered great for Aquaponics system as they create a lot of waste if overfed.
They’re easy to keep, cheap and are beautiful to look at and incorporate into your garden. This fish can eat insects, small marine life, or specified fish food. You can also grow a lot of your own food for them.
They are known for attracting parasites. Don’t use goldfish anywhere there’s the chance they can escape into natural water systems.
- Species of carp
- Ideal for large commercial ponds or 200+ gallon tank
- Optimum temperature: 20-25 °C
- Vital temperature 37-90° F (3-32 °C)
- Omnivorous fish
- Less desirable to eat
- Long lifespan and grows up to 20-36 inches
- Great resistance against common parasites
Koi are a high-value fish, compared to a fish meant for food like tilapia or catfish. You may end up with fish worth hundreds or even thousands of dollars. However, do not invest more than you are willing to lose in buying your fish. There can be mortalities until you get your system matures.
The proper oxygenation and off-gassing are vital in winter months and small ponds. Although technically edible, they are desirable for dining as they are difficult to prepare and are bony. Koi ponds can be transformed into beautiful aquaponics systems to improve water quality.
4. Channel Catfish
- Optimal Temperature: 75-86° F (24-30° C)
- Tolerate temperatures range 40- 93 °F
- Hardy widely farmed food & Sports fish
- Needs a large fish tank (250+ gallon)
- Fast Growing and max size of 40-50 lbs
- Requires 32-38% Protein
- Edible (Bonus! Catfish are rich in Vitamin D)
- Great feed conversion ratio (2lb feed/ lb fish)
- Difficult to breed but not impossible!
Catfish are benthic fish and occupy only the bottom portion of the tank. Hence raising them in a deeper or small tank at high densities is not suitable as they do not spread out through the water column. They can hurt each other with their spines in overcrowded tanks. So you should either use a tank with greater horizontal space than vertical space or raise them with other fish species that utilize the upper portion of the tank, commonly bluegill sunfish, perch or tilapia. Catfish can be trained to eat floating pellets.
As catfish don’t have scales like other fish, you should be extra gentle or minimize the handling. They need to be skinned to prepare for cooking. Their skin, whiskers and calm temperament make them fascinating to watch.
5. Rainbow Trout
- Cold water fish: 14–16°C (57-60°F)
- Vital temperature range: 10–18°C (50-64°F)
- Edible and have excellent flavor
- Carnivorous: need high 40-50% protein diet
- Among the fastest growing fish in the list (800-1000 grams in 14–16 months)
- Belongs to the salmon family
- Harder to maintain (needs high DO levels, sensitive to pH changes and water quality)
A trout is a great option for aquaponic systems in cold areas. This is exciting to watch the progress of this fast-growing fish with excellent food conversion ratios. Their great taste and value come with a lot of challenges to raise them. The optimum pH range is 6.5 – 8.5.
Unlike tilapia, trout will not thrive in dirty water and needs well-oxygenated water with a dissolved oxygen level that never falls below 5.5ppm. They jump out of the tank so you need a lid or cover on your set-up. They can’t handle warm water, so only consider this fish for very cold regions. You are left with a limited choice of vegetables to grow and poor plants’ growth at the temperatures preferred by this species. These carnivorous fish need commercial pellets fish food (or a home-made equivalent) and aquatic invertebrates (smaller fish, flies, mollusks, insects, and bloodworms). They can also have cannibalistic tendencies towards their own and other species of fish.
6. Jade Perch
- Native Australian fish
- Optimum temperature 70–80°F (21-27°C)
- Edible (Highest levels of omega-3 oils of any fish species in the world)
- Grow quickly (500g in 10 – 12 months)
- Don’t breed in captivity
- Omnivorous needs medium protein diet
- Max Growth Size: 35 cm
A hardy, omnivorous, fast-growing, tasty and highly-nutritious fish feeding on relatively inexpensive diets makes it a very attractive option for aquaponics. Australian aquaponics pioneer Murray Hallam and his fellow Aquaponists absolutely love it. It is difficult to find in the USA, but if you can get it you should give it a try. They have great temperament and live peacefully with similar type of fish.
You can expect to harvest them within 12 months under standard conditions. They make a nutritional meal at harvest time and even surpass the Atlantic Salmon when it came to healthy fish oils. It is so high in omega three oils that some growers are trying to breed a less oily fish out of them.
Jade perch will stop eating below 65°F (18°C) and can become inert and die at temps below that zone. Like a lot of Australian native fish, they will not breed in captivity unless injected with a special hormone.
These fish are hardy but not bullet-proof and are not able to live without dissolved oxygen pumped into their tank using conventional stones and an aerator. The optimum pH range is 6.8 – 7.8.
7. Largemouth Bass
- Popular North American native gamefish and part of the freshwater sunfish family
- Optimum temperature: 20-30 °C (70-86 °F)
- Tolerates temperature range 10 – 36 °C
- Minimum tank size: 1200 gallons
- Carnivorous: requires high ≥ 40% protein diet
- Edible (boneless, white flesh with high levels of omega-3 fatty acids)
The largemouth bass is an excellent choice for aquaponic farmers because of their high tolerance to low DO as well as good resistance to high nitrite levels. In the USA, They are cultured and sold as high-end sports fish due to the great demand and comparatively high selling price. Their wide temperature tolerance range also makes them suitable for both cold and warm seasons. Largemouth can grow to more than 2 pounds their first year under ideal conditions. The maximum size of female Florida largemouth is about 20 pounds.
The largemouth bass is suitable for ponds larger than 1 acre. They spawn in pond naturally without any need of hormone manipulations, then the adults or young are removed to prevent cannibalism. The catfish, goldfish, minnows, carp, bluegills, and tilapia are forage for these piscivores. Their need to be pellet-trained and expensive high protein diet requirement can be challenging. However, the value of largemouth bass offset these costs.
Read more about Largemouth Bass here.
8. Murray Cod
- Largest native Australian freshwater fish species
- grow very fast even in a closed environment (500g in 12 – 18 months)
- Optimum Temperature: 24-25° C
- Tolerate water temperature from 10 to 25°C
- can live for more than 50 years
- Edible Fish with great taste
- Can grow up to 50 kg
- Diet: High protein
They are only suited to raise in tanks as they need to be kept at high density to suppress territorial behavior. You must keep them fed well and satisfy their appetite otherwise they will attack and cannibalize each other. At large sizes, they consume any fish that fits in their mouth. Small Murray cod can peacefully co-exist with other fish like Silver and Golden Perch. Murray cod is recommended for people who have time for the maintenance involved, as they are highly vulnerable to fungal and bacterial infections too.
- Optimum Temperature 65 – 80 °F (18-27 °C)
- Tolerate Temperature range of 55-95 °F (13-35 °C)
- Easy to breed
- Require high 36-40% protein diet
- Slow Growth (2 years to market size)
- Bad Feed Conversion rate: 4lbs feed/1 lb fish
Bluegill is a good option for small-scale aquaponics. They are common and highly prized game fish throughout the United States and Canada. Bluegill is adaptable to ponds, cage culture, and tank systems. You can also keep Bluegill in a Koi pond to control algae growth. They will coexist very well with all of your pond critters like Koi, goldfish, and turtles. Pure strain bluegill will spawn numerous times even in tanks as small as 55-gallon aquariums. Bluegill gets cannibalistic after the nesting phase and juveniles need to be moved to a smaller tank.
Bluegill requires high protein and prefer a diet consisting more of invertebrates such as freshwater shrimp, larvae and small fish. They grow slower and do not offer a good of a conversion rate.
- Optimum Temperature: 18 to 26 °C
- Vital Temperature range: 10-30 °C
- Length: Up to 50 in and larger
- Age: 50 to 100 years
- Carnivorous special feed: High-grade quality of sinking feed with fats, vitamins, and minerals
- Needs a larger and deep Pond (260 gallons per fish)
Aquaponics is well suited to sturgeon because they can tolerate lower pH which makes micronutrients more available to the plants and thrives at the same temperature that is ideal for the plants. Like the paddlefish, sturgeon are cartilaginous skeleton fish without bones. They also produce a lot of waste for plants because of their feeding habits.
They need feeding prepared diets, intensive management, and high capital and operating costs, especially for mature females for production of caviar. They are efficient bottom feeders, consuming insect larvae, small fish and occasionally fish-related carrion. Moreover, they need frequent feeding (every 3 hours).
Sturgeon require high-quality water for optimum rearing conditions. Sturgeon needs a pond size of at least 10 times its length and a depth of minimum 50 in everywhere. The pond needs a layer of mud on the bottom with absolutely no sharp gravel or sand and very few plants. Sturgeon, especially smaller specimens, cannot swim backward and will be stuck and drown in a pond with plants or filamentous algae. A proper soil discharge and aeration are necessary to ensure dissolved oxygen in the pond. If you want to keep them in the tank, it should be of at least 5000 gallons. (You can keep Sterlet in decent sized tanks though)
These are just most common and widely used of the options you can consider. The local fish species living in the streams near where you live are the probably a perfect choice for your climate.
You can even consider fish as fancy as barramundi or Pacu if are willing to spend more money on more complicated or bigger tanks. Other aquaponics fish include crappie, Gobi, eels, Brook, Brown & Lake Trout, Coho Salmon, Muskellunge, Northern Pike, Smallmouth Bass, Snakeskin gourami, Snakehead and whatever other species you prefer. You can also incorporate various ornamental fish in aquaponics such as angelfish, guppies, tetras, Danios, swordfish, Cichlid, Oscar and mollies. Whatever you choose, pay attention to their temperature needs, growth rates, and diets.
You can also use freshwater mussels, prawns, and crayfish in an aquaponic system. Using mussels in aquaponics do a great job of helping to clean the water. They are a filter-feeder and will happily grow within flooded grow beds, as well as inside fish tanks. Check alternatives to fish in aquaponics here.
Not to use Species
Unless you are culturing seaweed, Marine or brackish species will not work. So don’t think of using a Red drum, cobia, flounder, Atlantic croaker, pompano, and marine baitfish.
Since minimum culture salinity is 5 ppt salinity. Most vegetables & herbs when exposed to 5 ppt salinity usually die.
And Yes! you may also not be able to use a shark or whale in your system. Are not they too big or deadly?
After deciding which fish species to get, you need to decide how many. The rule of thumb is one pound of live fish per gallon of water. Read more about fish to water ratio here. Prepare your aquaculture system with dechlorinated water, functioning aeration and filtration system as well as fingerling food. Here’s a handy source for organic fish food. Some more handy tips are as follows.
- Choose between small (1-2 inch) or advanced fingerlings (3-4 or 4-5 inch).
- Amount of feed per day drastically different between sizes – impacts nutrients available to plants.
- Always buy feed-trained fingerlings because you would prefer not to have to feed train them yourself.
- Not maintaining water quality will not harm a hardy fish, but don’t complain about the off flavor taste on afterward.
- The growth rates are highly dependent on temperature, DO, pH and feed quality. Although many fish tolerate low DO, Feed conversion efficiencies are reduced when dissolved oxygen (D.O.) concentration drops below 4 mg/L. The temperate zone fish usually grow more during the warmer seasons. Read more about role of dissolved oxygen in Aquaponics here.
- Some inputs are required to keep the system performing like air pumps, aquarium heaters and feed that is given to the aquatic animal.