Methods for controlling a density of algae growing in an aquatic environment are provided. Exemplary methods include applying an effective amount of glyphosate to a density of algae growing in an aquatic environment. The algae may include genus Nannochloropsis and/or Dunaliella. The algae may also include a glyphosate resistant strain of genus Nannochloropsis. The effective amount may result in an approximate concentration of between 0.1 millimolar to 0.3 millimolar glyphosate in the aquatic environment. Additionally, the aquatic environment may include seawater. The glyphosate may be applied to the aquatic environment before and/or after the aquatic environment is inoculated with algae. Alternative methods include applying an effective amount of glufosinate to a density of algae growing in an aquatic environment. Fig. 8