Octo Classic 100HOB Protein Skimmer

Hang-On-Back Design for Marine Aquariums Up to 105 Gallons

The Reef Octopus Classic 100 HOB is a hang-on-back protein skimmer designed for marine aquariums up to 105 gallons, featuring an advanced Aquatrance pinwheel pump for superior waste removal. Installation is effortless with no sump required; attach to your tank's back or side, connect the pump, and enjoy professional-grade water filtration. Built from durable acrylic construction, this trusted skimmer removes dissolved organics and proteins before they break down, promoting healthier fish and vibrant coral growth.

Bioload Handling:

The bioload of an aquarium refers to its ability to process waste in proportion to tank volume. Protein skimmers work best when properly matched with the bioload of the system.

(EXCLUDING SUMP)

• Heavy Bioload: 55 gallons
• Medium Bioload: 75 gallons
• Light Bioload: 105 gallons

Key Features:

• Easy Hang-On-Back Installation - No sump required, fits most tank configurations
• Low Profile Body - Compatible with most aquariums up to 105 gallons
• Aquatrance Pinwheel Pump - Advanced technology for optimal air-water mixing
• Quiet Operation - Includes air silencer 
• Premium Acrylic Construction - Durable, clear visibility for performance monitoring
• Professional Results - Removes proteins and dissolved organics before breakdown
• Reef & Fish Safe - Promotes coral growth and maintains fish health

Pro Tips:

• Allow two to four weeks for break-in before fine-tuning. New skimmers — especially pinwheel designs — go through a conditioning period where the pump surfaces and skimmer body develop a biofilm that stabilizes bubble production. During break-in the skimmate will likely be wet and light-colored. Set the water level adjustment to mid-range and leave it alone for the first two weeks before making changes.
• Keep the Aquatrance 1000s air intake clear. The external pump mounting makes it easy to check and clean the venturi air intake regularly. A partially blocked intake reduces air draw and noticeably drops skimming performance without any other obvious symptoms. The included air silencer should be removed and rinsed periodically.
• Match the skimmer to your actual bioload, not just tank volume. A heavily stocked fish-only tank at 75 gallons will push this skimmer harder than a lightly stocked reef at 105. Use the bioload table above as your primary sizing reference, not the maximum tank rating.