Copepods are very hardy marine organisms accustomed to the strong ocean currents found on natural coral reefs. Remember. Typically the water movement in an aquarium is significantly less than in the ocean. Therefore, the copepods have no problem navigating your aquarium, finding rocks, macro-algae, and other hiding places where they can live and carry out their life-cycle in your aquarium. They are also small enough to fit in between the blades of circulation pumps so they are not killed if and when they do pass through one.