Five Native South American Fish Species Suitable For Aquaponics

Aquaponics—the symbiotic integration of fish farming and hydroponic plant cultivation—faces a critical limitation: global overreliance on tilapia and catfish. A landmark 2021 review in Aquaculture International reveals how five South American native species offer scientifically validated solutions for ecological resilience, market diversification, and food security.

With freshwater fish consumption in South America critically low at just 3.2 kg per person annually compared to the global average of 8.2 kg, these species could transform regional nutrition while conserving vital resources.

The Urgent Need for Fish Diversity in Aquaponics

Traditional reliance on tilapia and catfish presents significant problems that demand alternative solutions. Health concerns top the list because approximately 89% of tilapia operations use 17α-Methyltestosterone for masculinization, leaving hormone residues in fish tissue.

Meanwhile, catfish raised in polluted waterways like Vietnam’s Mekong Delta frequently contain heavy metals exceeding World Health Organization limits by 300%. Environmental risks compound these issues since escaped tilapia have reduced native fish populations by 42% in Brazilian rivers.

Furthermore, market research shows rejection rates for tilapia reach 34% in Colombia and Peru due to consumer perceptions of it being “unnatural.”

These challenges highlight why diversifying aquaponic species is essential, particularly in South America where 28% of the population experiences malnutrition and sustainable food systems are urgently needed.

Scientific Selection Criteria for Aquaponics Fish

Selecting suitable fish species requires meeting specific biological and technical parameters. For traditional coupled aquaponics systems where (benefits) fish and plants share water, ideal fish must tolerate pH levels between 5.5 and 6.5 because this range optimizes nutrient absorption for plants.

Additionally, they need resilience against high nitrate concentrations exceeding 100 mg/L and significant temperature fluctuations.

In contrast, decoupled systems separate fish and plant units, allowing farmers to prioritize growth traits like stocking density measured in kilograms per cubic meter, feed conversion ratios indicating efficiency, and market-driven characteristics.

South American native species uniquely satisfy requirements for both system types due to their evolutionary adaptations to regional conditions. Here are some fish species suitable for aquaponics:

1. Jundia: The Hardy All-Rounder

The silver catfish (Rhamdia quelen), known locally as jundia, demonstrates exceptional adaptability. Thriving in water temperatures from 20°C to 26°C and pH levels between 5.4 and 7.0, it survives dissolved oxygen as low as 5.6 mg/L and ammonia concentrations up to 3 mg/L.

Growth metrics reveal it reaches market size of 800 grams within just eight months—significantly faster than tilapia’s typical 10-12 month cycle. Its feed conversion ratio ranges between 1.6 and 1.9, meaning it efficiently converts feed into body mass.

Nutritionally, jundia offers 18.9% protein content with only 4.2% fat, making it leaner than most catfish. Early trials show promise, including a biofloc aquaponics study with lettuce where jundia achieved zero mortality.

2. Yellowtail Lambari: The Rapid-Cycle Mini Powerhouse

This small characin species (Astyanax lacustris) grows remarkably fast, reaching harvest size of 10-15 grams in just 90 days. It thrives in pH conditions from 6.5 to 8.0 and dissolved oxygen levels of 4.8 mg/L, though it requires very low nitrate concentrations below 0.25 mg/L.

Its feed conversion ratio of 1.1–1.5 is the most efficient among all reviewed species, reducing feed costs substantially.

Nutritionally, lambari provides 16.3% protein and 5.7% fat, plus essential minerals like calcium and iron that benefit nutritionally vulnerable communities. Annual production in Brazil already reaches 595 tonnes, primarily supporting small-scale family farms.

3. Pacu: The High-Density Champion

Pacu (Piaractus mesopotamicus) supports intensive farming with a remarkable stocking density of 75 kg/m³—surpassing tilapia’s 70 kg/m³ benchmark. It prefers pH levels between 6.9 and 7.5 and dissolved oxygen at 5.9 mg/L.

Growth data confirms it achieves 1.3 kg within 12 months with a feed conversion ratio between 1.2 and 1.6. Its omnivorous diet requires only 32% protein content, lowering feed expenses.

Nutritionally, pacu provides 18.2% protein and 8.4% fat, offering a richer energy source than leaner alternatives. Crucially, it outperformed tilapia in integrated aquaponics trials, boosting scallion and parsley yields by 11% while maintaining excellent fish health.

4. Tambaqui: The Amazonian Giant

Adapted to the Amazon’s extreme conditions, tambaqui (Colossoma macropomum) tolerates acidic water with pH as low as 4.7 and up to 6.8. It survives dissolved oxygen at 4.8 mg/L and ammonia concentrations up to 1.2 mg/L.

This species reaches an impressive 2.5–3 kg market size within 24 months while requiring only 30% dietary protein—the lowest among all species reviewed. Its nutritional profile features 19.0% protein and minimal 2.7% fat, creating a heart-healthy option.

South America produces 142,100 tonnes annually, with EMBRAPA confirming 99% survival rates in compact aquaponic systems using local vegetables.

5. Snook: The Premium Luxury Fish

Snook (Centropomus spp.) commands premium prices at R$38/kg (€8.17) compared to tilapia’s R$6/kg. This diadromous fish tolerates salinities from freshwater to 40 parts per thousand and pH levels of 6.9–8.2. It grows to 500 grams within 12 months with a feed conversion ratio of 1.2–1.8.

Nutritionally superior, it delivers 22% protein—the highest among all studied species—and an exceptional omega-3 to omega-6 fatty acid ratio of 2.8, compared to tilapia’s ratio of just 0.4. Though currently untested in commercial aquaponics, its high fillet yield of 42% makes it ideal for luxury markets.

Furthermore, scientific comparisons reveal distinct advantages for South American species across key parameters. While catfish tolerate extreme densities of 300 kg/m³, pacu follows closely at 75 kg/m³ versus tilapia’s 70 kg/m³. Tambaqui requires only 30% dietary protein compared to catfish’s 40%, reducing feed costs significantly.

Growth rates vary substantially, with tambaqui reaching 2.5–3 kg but requiring 24 months, whereas lambari matures in 90 days at just 10–15 grams. Market values diverge sharply, with snook fetching R$38/kg versus tambaqui’s R$5.30/kg. These metrics prove native species offer tailored solutions for different aquaponic goals and market niches.

Matching Species to Aquaponic System Types

Different system architectures favor specific species based on their biological traits. Coupled aquaponics systems benefit (market) most from tambaqui’s extraordinary pH resilience, allowing it to thrive between 4.7 and 6.8 without system failures.

Similarly, jundia tolerates nitrate concentrations up to 86 mg/L, preventing nutrient toxicity in leafy green production.

Meanwhile, decoupled systems unlock potential for high-value species: pacu’s 75 kg/m³ density maximizes space efficiency in commercial setups, while snook’s premium pricing offsets its 45% protein feed requirement. Consequently, farmers can match species to their infrastructure and market objectives.

Despite compelling advantages, significant hurdles remain before widespread adoption. Research gaps are substantial, with only two published aquaponics studies on jundia and zero for snook.

Hybrids like “tambacu” (tambaqui-pacu cross) could boost yields by 20% but require environmental impact assessments before promotion. Policy limitations also hinder progress; Brazil allocates merely 0.8% of agricultural funding to sustainable aquaculture despite its potential.

Economic challenges include decoupled systems’ 15% higher startup costs, though they generate 40% greater profits through premium products. Addressing these barriers requires coordinated efforts between researchers, governments, and farmers. Furthermore, three key actions can accelerate adoption of native species.

• First, prioritize species-specific trials: test tambaqui in Amazonian coupled systems with native plants like Victoria amazonica, and validate snook protocols in coastal hubs.
• Second, advocate for policy reforms: governments should subsidize native fingerling production to address the current annual deficit of 120 million juveniles.
• Third, educate consumers through marketing campaigns: position jundia as “boneless catfish” to overcome cultural preferences for imported species.

As Dr. Maria Portella, co-author of the study, emphasizes: “These species reduce disease risks by 65% compared to tilapia due to regional adaptation.”

Conclusion

South America’s native fish species offer transformative potential for global aquaponics. Jundia, lambari, pacu, tambaqui, and snook provide scientifically validated solutions to tilapia and catfish limitations, from jundia’s pH resilience to snook’s premium value.

Their regional adaptation slashes disease risks while conserving water and nutrients. Small farms can leverage lambari’s 90-day harvest cycle for steady income, while commercial operations target snook’s luxury market.

With 29% less feed waste than tilapia systems and 50% lower water consumption, these species align with UN Sustainable Development Goals. As climate pressures intensify, investing in these fish transitions from optional to essential—a blueprint for resilient, hunger-free food systems.