Reef Octopus Reef Octopus eSsence S-130 Protein Skimmer - Reef Octopus $374.99 The Reef Octopus eSsence S-130 Protein Skimmer was designed for the modern day aquarist in mind. This remarkably compact in-sump protein skimmer is capable of skimming aquariums up to 160 gallons where sump space may be limited...