Live Phytoplankton provides the start of the food chain for the eco system in your marine tank. With the unique, live Colombo Phytoplankton, you can add this to your marine tank. The water in your marine tank is the natural environment for Colombo Phytoplankton. The Phytoplankton is produced in the Netherlands in a purpose built nursery using salt water from an ancient well. Other algae like Chlorella and Spirulina grow in fresh water this makes these less suitable for use in a marine tank.