Tonton Streaming Super Friends (1973) S1E16 - The Watermen

A strange spacecraft has been forced to land on Earth after a meteor hit the fuel tank of the craft. In an attempt to return from the planet Sagittarius, the craft begins gathering silicon from sea water to fuel the ship. Aliens from the water planet steal the silicon from Earth's oceans, upsetting the ecological balance and creating a red tide and famine among ocean creatures.