Reef Octopus Ozone Generator RSO-25 An advanced method of water purification for the Most Absolute - Crystal Clear Water. Ozone use raises the ORP of your aquarium water, increases oxygen levels, decreasing dissolved wastes, removes yellow coloration and effectively control numerous harmful pathogens.Though many ozone users utilize their skimmers as a type of reactor, we highly recommend using a dedicated reactor like our Octopus OR-150 for the best and safest results.