TANZANIA, ZANZIBAR: My first day on the beach in Pongwe I learnt two things. First, seaweed has value. Two, you can also farm it! The previous day I'd observed the local villagers not only sit out in the water when the tide was low planting seaweed, but also bringing back baskets of fully grown seaweed to the shore on their heads. Naturally I wanted in on this unique feature of the local economy. This is the story of how I became Zanzibar's greatest seaweed farmer.