Innovative compact hatchery: Enhancing fish production and sustainability in limited spaces

Mariculture provides a sustainable approach to address the food security and nutritional needs of a growing global population. Achieving true sustainability in production systems requires a balanced focus on environmental responsibility, social impact, and economic viability. This innovative hatchery design embodies these principles, minimizing environmental impact through efficient space utilization, resource conservation, and automation. The features support high-density, responsible juvenile's production in a confined area, making the hatchery both scalable and sustainable. 

This compact hatchery unit (9.2 m x 2.7 m x 3.6 m) was designed for high-density pilot-scale juvenile’s production, reducing labor costs and simplifying regulatory compliance. Its efficient layout overcomes typical barriers faced by larger facilities, providing an accessible entry point for new industry participants to generate data that can be used for future scaling up operations. 

The small hatchery is organized into four zones: (1) intensive rotifer grow-out, (2) Artemia hatching and enrichment, (3) rotifer enrichment, and (4) intensive larval rearing. Automation between tanks optimizes production efficiency. A single refrigerated unit maintains microalgae (Rotifer Diet™) at 4°C, continuously pumping this high-density feed to the rotifer tanks, ensuring a reliable and cost-effective supply. The rotifer section comprises three 250 L tanks, maintaining densities of 1,000-2,000 rotifers mL⁻¹, and can produce up to 100 million rotifers daily, sufficient to sustain optimal larval feeding densities of 15-20 rotifers mL⁻¹. Rotifers can be transferred directly from culture tanks to larval rearing tanks using peristaltic pumps or moved to enrichment tanks (three units, each 75.7 L) to enhance their nutrient content. The Artemia section includes three 132 L tanks, generating up to 17 million nauplii daily, achieving a feeding density of 5 nauplii mL⁻¹. 

The larval rearing tanks includes two 1.8 m³ tanks, maintaining a density of 100 larvae mL⁻¹. This system has demonstrated successful production runs, including 170,000 red drum (Sciaenops ocellatus) at 0.05 g each in 33 days, 10,000 red snappers (Lutjanus campechanus) in 45 days, 10,000 yellowtail snappers (Ocyurus chrysurus) in 35 days, and 25,000 Atlantic croaker (Micropogonias undulatus) juveniles in 25 days, all with high survival rates. By integrating high output with cost-efficient resource utilization, this compact hatchery provides a viable and sustainable pathway for the future of aquaculture.