What is the best fish for aquaponics? Selecting the right fish is vital to your success. Let’s consider what fish best fits your aquaponics system. Let’s start with an informative table to help you quickly compare some of the most popular fish species to put in your aquaponics system. PS: A more in-depth article about each species is available by clicking the name in the table below.
| Common name Binomial name | Temp | pH | Minimum Tank Size | Pros | Cons |
|---|---|---|---|---|---|
| Rainbow Trout Oncorhynchus mykiss | 10-18°C 50-65°F | 6.5-8.0 | 500 Liters 132 Gal | Fast-growing, delicious, high feed conversion | Requires cool, oxygen-rich water |
| Brook Trout Salvelinus fontinalis | 10-15°C 50-59°F | 6.5-8.0 | 500 Liters 132 Gal | Hardy in cold water, resilient to changing water conditions | Prefers colder climates |
| Brown Trout Salmo trutta | 12-17°C 54-63°F | 6.5-8.0 | 500 Liters 132 Gal | Unique flavor, cold and variable water tolerant | More challenging to raise and catch |
| Nile Tilapia Oreochromis niloticus | 21-30°C 70-86°F | 6.5-9.0 | 250-500 Liters 65-132 Gal | Fast-growing, disease-resistant, thrives in warm water | Requires heater in colder climates |
| Blue Tilapia Oreochromis aureus | 20-28°C 68-82°F | 6.5-9.0 | 250-500 Liters 65-132 Gal | Adaptable to low oxygen and salinity, mild flavor | Growth rate slightly slower than Nile Tilapia |
| Mozambique Tilapia Oreochromis mossambicus | 22-30°C 72-86°F | 6.5-9.0 | 250-500 Liters 65-132 Gal | Genetically improved growth, good disease resistance | High temperatures required, might need a heater |
| Yellow Perch Perca flavescens | 16-23°C 61-73°F | 6.5-7.5 | 400 Liters 105 Gal | Great flavor, ideal for colder regions | Small-size fish; slower growth compared to tilapia |
| European Perch Perca fluviatilis | 15-25°C 59-77°F | 6.5-7.5 | 400 Liters 105 Gal | Unique appearance, good taste | Can be aggressive towards other species |
| Channel Catfish Ictalurus punctatus | 24-30°C 75-86°F | 6.5-8.0 | 500 Liters 132 Gal | Hardy, fast-growing, bottom feeder (helps clean) | Sensitive to low temperature, requires large space |
| Blue Catfish Ictalurus furcatus | 20-27°C 68-80°F | 6.0-8.0 | 600 Liters 158 Gal | Large size, fast growth | Needs big tanks and strong filtration |
| Flathead Catfish Pylodictis olivaris | 18-25°C 64-77°F | 6.5-8.0 | 600 Liters 158 Gal | Tough and resilient, scavenger | Requires space, large fish, more difficult system management |
| Common Carp Cyprinus carpio | 17-25°C 63-77°F | 6.5-9.0 | 800 Liters 211 Gal | Highly adaptable, sturdy in poor conditions | Can uproot plants if hungry, large fish |
| Grass Carp Ctenopharyngodon idella | 20-28°C 68-82°F | 6.0-8.5 | 800 Liters 211 Gal | Natural weed control | May overeat your plants if hungry |
| Silver Carp Hypophthalmichthys molitrix | 10-25°C 50-77°F | 6.5-8.5 | 800 Liters 211 Gal | Good for filtering water, plankton eater | Jumper, may cause disruptions in the system |
| Giant Barramundi Lates calcarifer | 26-32°C 79-90°F | 6.5-8.5 | 1000 Liters 264 Gal | Great taste, fast-growing | Needs large tanks and heat; sensitive to cold |
| Lagoon Barramundi Lates calcarifer | 24-28°C 75-82°F | 6.5-8.5 | 600 Liters 158 Gal | Excellent flavor, adaptable, smaller size | Can be sensitive to water changes |
| Striped Bass Morone saxatilis | 16-23°C 61-73°F | 7.0-8.5 | 1000 Liters 264 Gal | Popular for eating, adaptable to brackish water | Prefers cooler water, larger tank needed |
| Largemouth Bass Micropterus nigricans | 20-27°C 68-80°F | 6.0-8.0 | 500 Liters 132 Gal | Mild flavor, fast-growing, good for fishing setups | Needs controlled water temperature, slightly picky on conditions |
| Smallmouth Bass Micropterus dolomieu | 18-24°C 64-75°F | 6.5-7.5 | 500 Liters 132 Gal | Great for fishing, sporty, mild flavor | Requires high oxygen levels |
| Goldfish Carassius auratus | 10-25°C 50-77°F | 6.5-8.0 | 200 Liters 53 Gal | Hardy, visually appealing, ornament fish | Not great for eating |
| Koi Cyprinus rubrofuscus var. koi or nishikigoi | 10-25°C 50-77°F | 6.5-8.5 | 400 Liters 105 Gal | Beautiful, ornamental, hardy | Not for consumption, can stir up sediments |
| Black Crappie Pomoxis nigromaculatus | 18-23°C 64-73°F | 6.5-8.5 | 300 Liters 79 Gal | Mild taste, visually striking | Requires high water quality, tricky to breed |
| White Crappie Pomoxis annularis | 18-23°C 64-73°F | 6.5-8.5 | 300 Liters 79 Gal | Delicate flavor, adaptable to different waters | Slow grower, needs careful water management |
| Bluegill Lepomis macrochirus | 16-28°C 61-82°F | 6.5-8.5 | 300 Liters 79 Gal | Hardy, fast-growing, great fish for beginners | Can be territorial, slower-growing than tilapia |
| Redear Sunfish Lepomis microlophus | 20-26°C 68-79°F | 6.5-8.5 | 300 Liters 79 Gal | Pest control (eats snails), mild flavor | Slower-growing, prefers warmer water |
| Pumpkinseed Lepomis gibbosus | 18-26°C 64-79°F | 6.5-8.0 | 300 Liters 79 Gal | Colorful, mild flavor, adaptable | It requires good water quality and is considered an invasive species in Europe. |
Things to consider
- pH: To keep nutrients available for your plants, your pH should be around 6.5-6.8. Most fish can handle this pH. Be aware that pH naturally lowers over time.
- Temperature: Ensure your specific fish can thrive in the range you’re able to sustain.
- Tank Size: The larger the fish or group, the bigger the tank required. Larger tanks are also better for water parameter stability.
- Pros & Cons: Each species has its strengths, like fast growth or ease of care, but also comes with potential drawbacks (temperature needs, space, aggressive behavior, etc.).
- IMPORTANT: Most fish can handle various water parameters, but rapidly changing parameters is a no-go! Rapid changes can kill your fish, so if you need to make any changes, do it gradually.
Trout – Cool-Weather Champions
Trout are cool-water favorites. They’re adaptable, grow fast, and best of all, they’re delicious. They’re also a great choice for colder climates or systems where water stays on the cooler side.
- Rainbow Trout: Vibrant and fast-growing, they love oxygen-rich water and are a top pick for sport fishers. They convert feed efficiently and even put on a bit of a show, thanks to their fighting spirit.
- Brook Trout: Ideal for beginners and colder regions, Brook Trout are tough and tolerate varying conditions well.
- Brown Trout: Tricky to catch and harder to raise, Brown Trout are for the more experienced. However, their unique taste and adaptability make the effort worthwhile.
Tilapia – Aquaponics All-Stars
Tilapia is hands-down one of the most popular choices. They grow fast, aren’t too picky about water quality, and taste great on your plate. Plus, their hardiness makes them ideal for first-timers.
- Nile Tilapia: Growth and reproduction experts, they’re perfect for continuous harvesting.
- Blue Tilapia: Adaptable to low oxygen and higher salinity, Blue Tilapia add versatility to your system.
- Mozambique Tilapia: Genetically enhanced, they grow fast, handle crowded tanks well, and provide a consistent harvest.
Perch – Perfect for Cooler Waters
If you live in a cooler climate or just like calmer, less rowdy fish, perch could be your answer. They’re adaptable and grow well in cooler environments.
- Yellow Perch: Big on flavor, they’re great for smaller systems due to their compact size and efficient growth.
- European Perch: Sporting red fins and a tasty mild flavor, these guys adapt to a wide range of conditions and are fairly easy to manage.
Catfish – The Clean-Up Crew
Catfish grow fast and help keep your system clean by gobbling up leftover waste. These bottom-feeders are tough as nails and can deal with lower oxygen levels.
- Channel Catfish: Quick growers with a sweet, delicate flavor –perfect for the table.
- Blue Catfish: Larger and faster-growing than their cousins, they’re great for bigger systems.
- Flathead Catfish: With their distinctive broad heads and close-knit behavior to keep their tank pristine, they’re a catch for larger systems.
Carp – The Aquaponics Engineers
If system balance is a priority, carp could be an excellent choice. They’re resilient, adaptable, and known for maintaining water quality.
- Common Carp: Omnivores that keep the balance by eating a bit of everything.
- Grass Carp: Great natural weeders but beware—they can munch on your plants too!
- Silver Carp: Known for their incredible jumping skills (watch out!), they filter plankton and improve water quality.
Barramundi – Top-Tier Taste
Sauce it, grill it, bake it—Barramundi is a culinary gem with excellent adaptability and superb growth rates. They’re especially suited for warmer water systems.
- Giant Barramundi: These aggressive eaters grow big and are perfect for larger tanks. If the conditions are right, they can reach 1.8 m/5.9ft and weigh up to 60kg/130 lbs. But that’s not normal, especially not in an aquaponics system.
- Lagoon Barramundi: If you’re tight on space, this smaller variety delivers the same exquisite taste with a bit less aggression.
Bass – Anglers’ Delight
Bass are fantastic for sport fishing and culinary purposes. Their delicious meat and robust nature make them a must-have for bigger aquaponics systems.
- Striped Bass: Bold in both behavior and flavor, they’re perfect for slightly cooler setups.
- Largemouth Bass: Prolific feeders with a sweet taste, they demand careful water management.
- Smallmouth Bass: The more aggressive cousin, their mild flavor and energetic behavior make them fun to grow and catch.
Goldfish & Koi – Eye Candy with Extra Benefits
Goldfish and Koi aren’t just beautiful; they also help with algae control, making them functional decorations for your system.
- Common Goldfish: Pretty hardy with splashes of color.
- Comet Goldfish: Sleek swimmers with long tails, they add elegance to any system.
- Koi: Vibrant and mesmerizing, Koi are perfect if you’re looking for that “wow” factor in aesthetics.
Crappie – Underrated Aquaponics Fish
Crappie are often overlooked, but they’re fantastic for both eating and keeping your system running smoothly.
- Black Crappie: Spotted and sleek, they’re delicious and resilient in various conditions.
- White Crappie: Slightly sweeter than their black cousins, white crappies are adaptable and a great addition to multi-species systems.
Bluegill & Sunfish – Tiny but Mighty
These colorful little fish are fun to raise and help control pesky bugs in your system.
- Bluegill: Fast growers and enthusiastic feeders, they bring color and flavor to the party.
- Redear Sunfish: These “shellcrackers” will even help with pest control by eating snails.
- Pumpkinseed: Known for their eye-catching patterns, they may also steal the show with their mild flavor and adaptability.
Bonus tips
If you already have a freshwater aquarium with preferably soft water, you can use your regular aquarium and pet fish for aquaponics! Just build a small aquaponics system on top of your fish tank, and you’re done.
However, don’t expect the best result from a small aquarium. Smaller fish don’t create that many nutrients unless you overfeed and/or “overstock” your tank. You will also need those nitrates (among other things) to grow plants, so changing 50% of the water weekly won’t help your plants, i.e. less work for you.
But don’t let your nitrates get out of control; consider the fish and their tolerances first. If your nitrates get out of control stop feeding at once and don’t feed for a few days. You might also need to change some water to reduce the nitrates if your plants can’t remove them quickly enough, if you have spare room in your system; plant some more plants!
There are too many types of fish to mention them all, but most ornamental fish will do as long as they thrive in the preferred pH and tolerate higher nitrates (most do). You probably won’t be growing lots of vegetables or highly nutrient-demanding plants. But starting with a small row of salad on top of the tank is an excellent way to try aquaponics before you invest in a larger dedicated system.
If you experience ammonia, nitrite, or nitrate spikes without doing “something different,” you need to check your filters and your media grow beds for dead zones meaning no water movement and no aeration, aka anaerobic zones. This is often caused by large plantroots that have grown so intricate it holds on to decomposing matter(i.e. fish poo) and other humic substances preventing water flow, remove the plant and the affected grow media, wash or replace the media and plant new plants. To prevent or limit this in the future consider adding solids removal filter if you don’t have one.
Did you know that the key inhabitants of an aquaponics system are not the plants or the fish, but the bacteria? Provide them with nutrients and the proper environment for them to grow, and your system will stay stable for as long as you like. There are a lot of people out there saying the nitrogen cycle is all you need, but that is not fully true, first after a year or two your system can be considered mature and stable. And it will continue to mature long after this period too, it will keep adding more complexity and bacteria and fungi that breaks down matter into even more usable nutrients. Nature in incredible!