In September 2018, a farm visit in China introduced us to a technology that would reshape how we think about pond space: the In-Pond Raceway System, or IPRS. Two years later, in July 2020, we finished building our own.
A conventional pond spreads fish thinly across its whole surface, which caps how much it can ever produce. IPRS flips that. Long, narrow concrete raceways sit inside a larger pond, and fish are held at much higher density inside them, with water continuously pushed through by paddlewheels or pumps. The open water around the raceways does the heavy lifting of water treatment — settling waste, growing plankton, and re-oxygenating water before it cycles back through.
In a normal pond, water quality is the ceiling on stocking density — crowd the fish and the water turns against you. IPRS manages water quality actively, inside a contained space, so the ceiling moves. That's the entire reason 1.25 acres of IPRS pond can produce 20–25 tons of tilapia, several times what the same acreage would yield with conventional methods.
Feeding, health checks, and harvesting all happen inside a defined raceway rather than across an open pond — which means problems get spotted earlier, and harvests are more predictable and easier to plan around.
IPRS isn't a replacement for every pond on a farm — it's one tool in a broader system. At LarGro, we run both conventional ponds and IPRS raceways side by side, and we walk visiting farmers through exactly how the two compare, on the actual ponds, during our training sessions in Thatta. Book a visit →
