How does water influence the growth of spirulina bacteria?

These photos show spirulina under the microscope. The name spirulina describes the genus of edible aquatic cyanobacteria. The chlorophyll is responsable for the green color which is why spirulina used to be called green-blue algue. However, it is now widely known that they are bacteria, not algue.

My board game is supposed to be a competition between living spirulina. I will be focusing on the growth of spirulina. Therefore, I divided the spirulina in four parts and inserted each part in a tube with minerals and different types of water.

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