BIOFLOC

Biofloc technology turns the waste your fish and shrimp produce into food. Instead of flushing dirty water out of the tank, a biofloc system grows a dense community of bacteria and microbes that consume the ammonia from fish waste and uneaten feed, then clump into protein-rich particles — the bioflocs — that the stock eats. The result is a near-zero-water-exchange system that recycles nutrients in place, which is why biofloc aquaculture has spread from research ponds to commercial tilapia and shrimp farms across Asia, Africa and Latin America.

How biofloc technology works

The mechanism is simple to state and demanding to run. By adding a cheap carbon source — molasses, wheat flour or cassava — you raise the carbon-to-nitrogen (C:N) ratio of the water to roughly 15–20:1. At that ratio heterotrophic bacteria multiply fast and pull ammonia straight out of the water to build their own cells. Those bacteria, together with algae and organic particles, aggregate into suspended flocs. Two useful things happen at once: the toxic ammonia is removed, and the floc itself becomes a 25–50% protein feed the fish graze on between meals. The system only works while the water is aerated and moving, so dissolved oxygen has to stay above 4–5 mg/L, twenty-four hours a day.

Why farmers move to a biofloc system

• Water: exchange is cut by 80–90% versus a flow-through or earthen pond — decisive where water is scarce, metered or pumped.
• Feed: floc protein can replace 10–30% of formulated feed, the single biggest running cost on most farms.
• Density and biosecurity: higher kg/m³ on the same footprint, in a closed system that keeps pathogens out.

The trade-off is honest: biofloc swaps a water problem for a power problem. Aeration must never stop, and the floc has to be held inside a working window — about 200–500 mL/L of settled solids — or the system tips from clean to anaerobic.

SIGMA biofloc equipment

A biofloc system is forgiving on water but unforgiving on oxygen, so the equipment list is short and non-negotiable: continuous aeration from a root blower feeding a grid of nano aeration tubes, a tank that holds clean water (commonly a 650–750 GSM PVC tarpaulin or an HDPE-lined pond), water-testing instruments, and backup power. SIGMA manufactures and exports this hardware as an HDPE and biofloc aquaculture specialist, with biofloc tanks shipped to groups such as Japfa and to farms in Ghana, Mozambique and Bangladesh. See our full range of biofloc aquaculture equipment, or tell us your species and tank size for a quote.