The Great White protein skimmer is a product line from Reef Octopus, specifically their more accessible and simplified skimmer series. If you've searched for "great white protein skimmer," you're likely looking at either the Reef Octopus Classic series or an older product by that specific branding. Reef Octopus has built a strong reputation in the saltwater hobby for producing consistently performing skimmers across several price points, and the Great White label represents their entry-level to mid-range category.
This article covers what a protein skimmer does, how the Reef Octopus Great White/Classic series performs in practice, which size to choose for your tank, and how it compares to other skimmers in the same price range.
What a Protein Skimmer Actually Does
A protein skimmer removes dissolved organic compounds (DOCs) from saltwater before they break down into ammonia and nitrate. It works by injecting tiny air bubbles into a body of water inside the skimmer body. Organic molecules attach to the surface of these bubbles. As bubbles rise, they carry the organics upward into a collection cup, where they concentrate into a dark, smelly liquid called skimmate. You empty that cup periodically.
The result is lower nitrate and phosphate levels, clearer water, and a reduced bioload on your biological filtration. In a reef tank with corals, this matters considerably because corals are sensitive to dissolved organics and elevated nutrients cause nuisance algae outbreaks.
In a FOWLR (fish only with live rock) tank, a skimmer still helps, but you have more tolerance for slightly elevated nutrients. Skimmers are essential for reef tanks and highly recommended for any marine setup.
The Great White / Reef Octopus Classic Lineup
Reef Octopus has several lines, and the "Great White" designation has been used variously across their catalog. The current equivalent is the Reef Octopus Classic (BH series for hang-on-back and Classic 100/150/200 for sump-rated models).
Classic 90 (HOB)
The Classic 90 is a hang-on-back model rated for systems up to 90 gallons. It attaches directly to the tank or sump wall without requiring submersion. This is useful for tanks without sumps. Recommended water level: 6-8 inches at the skimmer inlet. The included Reef Octopus eSS100 pump delivers consistent micro-bubble production.
Classic 100-S (Sump Model)
Rated for reef systems up to 100 gallons. Submersible in 6-8 inches of water in the sump. The Classic 100-S uses the eSS1000 needle-wheel pump, which Reef Octopus manufactures in-house. Needle-wheel pumps pull water and air through the venturi simultaneously, producing extremely fine bubbles with good consistency.
Classic 150-S (Sump Model)
For tanks up to 150 gallons with moderate stocking. In a heavily stocked system, size down to treating the 150 as a 100-gallon skimmer. Physically larger, produces more skimmate volume per day, better suited for FOWLR tanks with messy fish like triggers, puffers, or large angels.
Classic 200-S (Sump Model)
Reef Octopus rates this for systems up to 200 gallons. Recommended for 100-150 gallon reef tanks or up to 200 gallons FOWLR. Uses the eSS2000 pump. This is where the Reef Octopus line starts to overlap with their Regal series, which is engineered for more demanding applications.
How to Set Up a Reef Octopus Classic Skimmer
Water Level
Protein skimmers are sensitive to water level. Too high and the skimmer floods the collection cup with diluted, watery skimmate. Too low and it barely produces foam. Most Reef Octopus Classic sump models operate best at 6-8 inches of water depth. Check this with a ruler if you're having consistency issues.
Break-In Period
New skimmers take 1-3 weeks to break in. During this time, they often overflow with microbubbles and watery skimmate. Don't adjust settings constantly during break-in. Set the bubble level roughly where you want it, let it run for a week, then fine-tune. Skimmate will become darker and more concentrated as the skimmer matures.
Collection Cup Cleaning
Clean the collection cup every 1-2 weeks. Dried skimmate becomes sticky and can clog the neck, changing the water level inside the skimmer and making it inconsistent. A quick rinse under warm water with a small brush keeps it flowing correctly.
Adjusting Output
The water level inside the skimmer body is controlled by an adjustable riser pipe or gate valve depending on the model. Raise the water level for drier, darker skimmate (less volume, more concentrated). Lower the water level for wet, lighter skimmate (more volume, less concentrated). Most hobbyists aim for skimmate that looks like dark tea or coffee.
How the Reef Octopus Classic Compares
vs. Bubble Magus Curve 5
The Bubble Magus Curve 5 is frequently compared to the Reef Octopus Classic 100-S. Both are sump skimmers in a similar price range ($100-150). The Curve 5 uses a pinwheel pump (similar to needle-wheel) and performs comparably for a 100-gallon lightly stocked reef. The Reef Octopus generally produces more consistent skimmate quality and has better build quality at the pump level. The Bubble Magus is slightly easier to clean.
vs. Eshopps Cone Skimmer S-200
The Eshopps S-200 runs cheaper, around $80-100. Performance is acceptable for FOWLR tanks and lightly stocked reefs. Build quality is below the Reef Octopus Classic, and long-term reliability is less consistent based on user reports across reef forums like Reef2Reef.
vs. SCA-301 (Bashsea)
The SCA-301 is a popular budget skimmer at under $80. It works decently for tanks under 60 gallons but tends to be finicky about water level and inconsistent in skimmate production compared to the Reef Octopus needle-wheel design.
For a full comparison of skimmers across price ranges, see our Best Aquarium Equipment guide.
Common Troubleshooting
Skimmer not producing foam: Check water level (should be 6-8"), confirm the pump is primed (remove and reinstall if needed), and give it a full week break-in period. Adding a little food-grade salt to the skimmer body can help kick-start foam production.
Skimmer overflowing constantly: Water level is too high. Lower the outlet pipe or gate valve. Also check that no additives (certain medications, tank supplements) are causing surface tension issues. Medications like Melafix or coral dips can completely suppress skimmer foam production for days.
Loud rattling noise: Check for a pebble, snail shell, or piece of rock rubbing against the impeller. Turn off the pump, remove it, and clean the impeller chamber.
Check the Top Aquarium Equipment guide for additional equipment recommendations that pair well with a protein skimmer in a reef setup.
FAQ
How often should I clean the Reef Octopus Classic skimmer pump?
Clean the pump impeller every 2-3 months. Remove the pump from the skimmer body, separate the impeller chamber, and rinse the impeller under warm water with a soft brush. Calcium deposits on the needle wheel reduce efficiency noticeably over time.
What is the right skimmate color and consistency?
Dark brown to black, with a consistency like thin motor oil. Very light, watery skimmate means you're skimming too wet (lower the water level inside the skimmer). No skimmate or barely any production after break-in usually means water level is too low or a water chemistry issue (low salinity, certain additives) is suppressing foam.
Can I use the Classic skimmer on a freshwater tank?
No. Protein skimming relies on the surface tension properties of saltwater. Freshwater doesn't foam in the same way, and a protein skimmer will not produce useful skimmate in a freshwater system. They are marine-only equipment.
Is a protein skimmer necessary for a FOWLR tank?
Not strictly necessary if you do large, frequent water changes (25-30% weekly). But for most hobbyists who do 10-15% weekly changes, a skimmer significantly reduces nitrate accumulation and makes maintenance much easier. A Reef Octopus Classic 90 or 100-S is a worthwhile addition to any FOWLR tank.
Bottom Line
The Reef Octopus Classic (sold under the Great White branding in some markets) is a well-made, reliable entry to mid-range protein skimmer that performs consistently with minimal fuss. The needle-wheel pump design produces fine, stable foam, and Reef Octopus's build quality stands up to years of continuous use. For a 75-150 gallon reef or FOWLR tank, the Classic 100-S or 150-S is a smart buy. Set it at the right water level, clean the pump quarterly, and it will run in the background without demanding much attention.