The plant
Duckweed is a family of small floating plants, among the smallest flowering plants on Earth. The common genera are Lemna, Spirodela and Wolffia. Each plant is a flat green frond, a few millimetres across, that floats on still or slow water.
Duckweed rarely flowers. It multiplies by budding: a mother frond pushes out daughter fronds, which break away and bud again. In good conditions a covered surface can double in two to three days. That speed, and the fact that it grows on water rather than farmland, is why duckweed is studied as a source of protein for animal feed.
Its protein content varies with species, water quality, nutrients and season. Batches from our own ponds have tested at 35–40% crude protein on a dry basis.
Why it matters here
Pakistan imported more than two million tonnes of soybeans in 2024–25, mostly for poultry feed, and soybean meal is also used in fish and dairy feed. That protein is priced in dollars, so feed costs move with the exchange rate and with global commodity markets.
A protein that grows locally, on water, and can be harvested continuously is worth taking seriously as part of the answer. It won't replace imports on its own, but it can reduce how much of a feed bag depends on them.
How we grow it
Our site near Islamabad has two lined raceway ponds with about 16,000 square feet of water surface. A paddlewheel keeps the water moving. A solar-powered borewell supplies it. Smaller mother-culture ponds hold back-up stock so we can restock a raceway if it is set back.
The site team records each pond's pH, water temperature, plant colour, algae, pests and inputs.
What the weather teaches you
Open ponds face the weather. Summer heat of 40–44 °C and monsoon storms are part of the job here, and both have set our ponds back. Both raceways now sit under shade nets, and the mother-culture ponds exist because of what recovery after a storm takes. Growing outdoors is harder than growing in a greenhouse. It is also the only way to learn what works on a real farm.
From crop to feed
Fresh duckweed is about 90% water. That makes it heavy to move and quick to spoil, so it can only be used close to where it grows. Drying it into a stable meal is what turns it into an ingredient, and pressing that meal into pellets is what turns it into a feed that can be stored and shipped. That is the route to GreenFin, our duckweed-based fish feed.
What is still being worked out
- Inclusion rates for each fish species, set by controlled feeding trials
- The full amino-acid profile, especially methionine, and digestibility
- Pellet durability and water stability in pond conditions
- Batch-to-batch consistency as volumes grow
University partners are running feeding trials with GreenFin now. The Evidence page lists each one and its status.