With the global demand for fish on the rise and wild fish stocks depleting just as fast, the need to find an alternative to damaging shallow water fish farms is as urgent as ever.

Marine engineer Steve Page believes he has found a solution. The Aquapod is a giant structure which can hold up to 70,000 fish. It is submerged in deep water so that any uneaten food and fish waste is washed away by strong ocean currents, minimising the damage to local ecosystems.

Working in Mexico's Baja Peninsula, Steve and his team are hoping their method of farming will help restore wild stocks to the ocean by preventing overfishing and offer a lifeline to fishing communities across the world.

Russell Beard goes deep sea diving in the Sea of Cortez to see the Aquapod in action and back on land visits the hatchery producing the fingerlings which would make their alternative farming operation totally sustainable.

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