Recirculating systems for sustainable farming
With little farming land and limited fishing grounds, Singapore is turning to sustainable aquaculture to help stabilise the country’s seafood supply by reducing its dependence on seafood caught from seas and rivers.
Emeritus Professor Lam Toong Jin of National University of Singapore believes that fish can be grown in fish farms more sustainably. Professor Lam and his team were awarded grants from Temasek Foundation Innovates to develop two key projects. The first project, which began in 2012, led to the development of a vertical recirculating aquaculture system for the production of Soon Hock fish (Marbled Goby), while the second project in 2013, looked into co-culturing the Soon Hock fish with other seafood (e.g. pacific white shrimp and tilapia) and plants.
The aquaponics system created by Professor Lam and his team combined conventional aquaculture with hydroponics. Water is fed into a hydroponic system where the waste by-products of the Soon Hock fish are broken into nitrates, which are then utilised by plants as nutrients, while the water is recirculated back through the system. Additionally, the waste by-products may also be fed to aquatic animals such as tilapia, shrimps and bivalves.
With this aquaponics system, fish farmers are able to channel the wastes from the Soon Hock fish as food for plants and other types of fishes for growth, while managing the water quality successfully. Professor Lam has also proven that this system is scalable not simply for small home systems, but for large farm systems as well.
Professor Lam and his team have been able to spawn the fish and raise the larvae through metamorphosis to the fry stage (the point where they can be cultured in farms to marketable size). The hatchery and nursery protocols have been worked out, and they have been able to produce thousands of fry. They have also been able to wean the fry to feed on artificial pelleted feed. Subsequently the fry can be grown to marketable size easily through the feeding of feed pellets.
With the conclusion of the research in 2016, Professor Lam is currently exploring collaborations with commercial entities on further developing this system for the culture of cockles, shrimps and other seafood.