The sea off Thailand's popular tourist island of Ko Lan turned a bright, pungent green this week as heavy rains and floods helped spark a plankton bloom that kept some swimmers out of the sea. Napat Wesshasartar reports ▻ ↧ Plankton bloom turns Thai island waters a bright, smelly green Heavy rains ‌and floods helped spark a plankton bloom that kept some swimmers on shore in the popular ​tourist island of Ko Lan.