Citizen Farm in Queenstown, Singapore Uses Closed-Loop Approach To Feeding Its Fish
Citizen Farm is trying to take Closed Loop aquaponics to the next level by creating a way to sustainably provide protein-rich food for their fish. They use their on-farm produce waste, along with that from local restaurants and grocers to grow Black Soldier Fly larvae. The larvae compost the food waste and are also the perfect protein-rich food for the fish.
The Singapore Government is ramping up efforts to reduce food waste as it tries to raise awareness over the issue. Citizen Farm is the first in Singapore to incorporate insects as part of the farming practice to help compost food waste but also to create a sustainable feed for its fish.
Now Black Soldier Fly Larvae (BSFL) is not a new practice to aquaponics, but it is mostly utilized by DIYers and home hobbyists. Most commercial farms do not produce enough waste to produce enough BSFL to keep their fish fed. That coupled with the extra labor makes it more efficient for most commercial growers to just use standard fish feed. Those growing indoors or in greenhouses also typically avoid the practice due to the composting smell.
Citizen Farm has overcome these obstacles in large part by sourcing extra produce and food waste from local restaurants and supermarkets, turning this waste into nutrient-rich fertilizer with the BSFL as a by-product they can use to feed their fish.
Once the larvae transform into pupae, the insects are fed to jade perch fish which the farm rears. The fish subsequently secrete waste that becomes fertilizer for its vegetables.
Leftover agriculture waste – or produce that cannot be sold – is fed to the larvae, which then produces waste that becomes fertilizer.
The farm produces about 150kg of produce and fish a month, which is also how much food waste it needs to keep its insect farm at full capacity. So you can see how most growers would not be able to find enough food waste from their operation to farm insects. The farm mainatains10kg of the pupae stage flier at any given time.
According to the head of Citizen Farm Darren Ho, the fly is also “easy to manage” as it does not transmit diseases, possesses a short life cycle of about six weeks and is a “shy insect” as it avoids human habitats.
Singapore generated 791,000 tonnes of food waste last year – about two bowls of rice daily – and this is set to grow along with the country’s size and affluence.