The Indian Major Carp polyculture is one of the most underappreciated achievements of 20th-century aquaculture science. The basic insight — that catla feed at the surface, rohu in the column and mrigal at the bottom — has not changed. What has changed, and badly, is its execution.
The 2:3:1 ratio
Two parts catla, three parts rohu, one part mrigal. The ratio is not arbitrary: it matches the trophic distribution of a healthy Bengali pond. Crowd any layer and the pond pays.
Why monoculture fails the kitchen
Industrial monoculture maximises one species per pond. The fish grow faster, the flesh is softer, the fat profile is wrong. A rohu raised in a pond that holds nothing else loses what makes a rohu worth cooking.
“A rohu raised alone is a rohu only in name.”
The kitchen test
Our blind kitchen panel, run quarterly with three Kolkata chefs, scores polyculture rohu meaningfully higher on flesh firmness, oil distribution and the cleanliness of the broth it produces. The science finds the kitchen, eventually.
- 2:3:1 catla–rohu–mrigal matches a healthy pond's trophic structure.
- Monoculture optimises growth at the cost of culinary quality.
- Blind kitchen panels routinely prefer polyculture fish on three quality axes.
