Methods for growing and harvesting algae and methods of use

A method for growing microalgae, comprising:

• introducing an amount of chitosan to an aqueous environment suited for growing microalgae;
• cultivating microalgae in the environment in the presence of chitosan over a period of time;
• and
• producing aggregated microalgae in the aqueous environment.

A method for increasing the lipid content of microalgae, comprising:

• introducing an amount of chitosan to an aqueous environment suited for growing microalgae;
• providing microalgae to the environment, wherein the algae microalgae has an initial lipid content per unit mass of microalgae;
• cultivating the microalgae in the environment in the presence of chitosan over a period of time;
• and
• increasing the lipid content per unit mass of microalgae grown with chitosan as compared to the initial lipid content of the microalgae.

A method for altering the lipid profile of microalgae, comprising:

• introducing an amount of chitosan to an aqueous environment suited for growing microalgae;
• providing microalgae to the environment, wherein the microalgae has an initial lipid profile comprising a plurality of lipid species;
• cultivating the microalgae in the environment in the presence of chitosan over a period of time;
• and
• altering the lipid profile of microalgae grown with chitosan as compared to the initial lipid profile of microalgae.

A method for removing constituents from water, comprising:

• introducing chitosan to an aqueous environment suited for growing microalgae, wherein the environment contains constituents desired to be removed;
• cultivating microalgae in the environment in the presence of chitosan over a period of time, wherein the constituents are taken up by the microalgae;
• and
• harvesting the microalgae to remove the constituents from the water.