Custom, engineer-specified foam fractionators (protein skimmers) built in Australia for recirculating aquaculture systems and commercial-scale aquariums.
Industrial Plastics has fabricated engineer-specified thermoplastic process equipment in Brisbane since 1971. We build protein fractionators (also called foam fractionators or protein skimmers) at the scale a commercial RAS farm or public aquarium needs: full-height columns in HDPE and PVC, welded to German DVS standards, with acrylic sight glasses and flanged process connections ready to plumb into your life support system. Whether you need a single column for a quarantine loop or a matched bank of units for a main display, we make it to your hydraulic and biological design.
What a protein fractionator does
A protein fractionator removes dissolved organic waste from water before it can break down and load the rest of your system. Fine air bubbles are injected at the base of a tall column. As the bubbles rise, dissolved organic compounds (proteins, fats, fish mucus, uneaten feed and other surface-active molecules) attach to the air-water interface of each bubble. The bubbles carry that material up the column into a dense foam, which collects in the head of the unit and is drawn off into a waste cup. Clean water returns to the system. Because the process physically lifts waste out of the water rather than converting it, it takes load off every downstream stage.
In a recirculating aquaculture system (RAS) or a closed aquarium loop this matters because mechanical screens and biofilters do not capture the finest fractions. More than 95 percent of the particles in a typical RAS are smaller than 20 microns, and a large share is dissolved or colloidal. Foam fractionation is one of the few practical ways to strip that fine and dissolved organic carbon out of the water column, which is why it is a core stage in most marine and brackish recirculating designs.
Why it belongs in a RAS or aquarium loop
- Removes dissolved organic carbon (DOC) and fine solids that biofilters and drum filters miss, lowering total organic carbon and keeping water clear.
- Reduces the load on the biofilter by exporting organics before they mineralise into ammonia and nitrate, which helps hold water quality stable at high stocking density.
- Cuts turbidity and bacterial load. Published RAS studies report meaningful reductions in particle count, turbidity, bacterial activity and biological oxygen demand from foam fractionation alone.
- Adds dissolved oxygen and strips carbon dioxide through the intense gas exchange in the column, a useful secondary benefit in an oxygen-limited system.
- Provides an ozone contact stage. Many operators inject ozone into the fractionator so oxidation and foam removal happen in the same vessel, improving disinfection and colour removal. Ozone-rated designs require the right materials and off-gas handling, which we detail with you at the design stage.
Marine, brackish and freshwater
Foam fractionation works best in salt water. Dissolved salts stabilise the fine bubbles and the foam, so marine aquaria and marine or brackish RAS (finfish, prawn, mud crab, abalone, live seafood holding) are the classic applications and where a fractionator earns its place most easily. In full freshwater the foam is less stable and fractionation is less efficient, so freshwater operators either accept a lower duty or use design measures to compensate. We size and configure the unit for your actual salinity rather than a catalogue assumption.
How we build them
Every unit is fabricated to your process design, not pulled from a shelf. A typical Industrial Plastics fractionator is a tall welded column made up of a bottom cylinder, a transition cone and a top cylinder, sized so the bubble contact time and foam head suit your flow and salinity. Construction detail we routinely supply:
- Body: HDPE or PVC column and cone, thickness engineered for the head and duty, welded by DVS-qualified welders with per-weld traceability.
- Sight glasses: clear acrylic windows so operators can see the foam line and tune the unit without guesswork.
- Process connections: HDPE and PVC pipework, flanged inlets, outlets and recycle lines, with stainless steel backing rings where flange loads require them.
- Internals: perforated distribution piping, air or ozone injection points, and a drainable foam collection head.
- Options: venturi or air-injection feed, ozone-rated build, adjustable foam-cup height, level control and instrument tappings, skid mounting and matched multi-unit banks.
Because we design and weld in-house under one ISO 9001 quality system, the columns in a multi-unit bank come out matched and repeatable, and every weld is traceable to the welder and the procedure. That is the difference between an engineered life support component and a bought-in box.
Representative projects
In 2016 Industrial Plastics fabricated a complete set of protein fractionators for the Jakarta Aquarium, the landmark indoor aquarium at Neo Soho in Jakarta, supplied through aquarium developer Perculas Limited. The Jakarta Aquarium is one of Indonesia’s largest indoor aquatic attractions, home to thousands of marine and terrestrial animals across immersive display and holding systems, and its life support had to hold water quality to an international standard for a permanent public collection.
We built twelve units in total across a family of sizes engineered to the aquarium’s different loops, from large primary columns down to smaller units for dedicated systems:
| Model | Role in the system |
|---|---|
| FF1200 | Largest columns, primary display and high-load systems (supplied in multiples) |
| FF600 (long and short) | Mid-size columns for medium-load loops |
| FF500 (long and short) | Compact columns for smaller systems |
| FF400 (short) | Smallest units for dedicated or quarantine loops |
Each unit combined HDPE and PVC construction, stainless steel backing rings at the flanges and clear acrylic sight glasses in the top cones, with CNC-cut componentry, perforated distribution piping and full design and drawing, annealing and handling as part of the build. The set was fabricated, hydro-tested and finished at our Hemmant workshop before shipping to site.
The project shows what we bring to an aquarium or aquaculture fit-out: a matched family of large fractionators, engineered to different duties, delivered as one traceable ISO 9001 package rather than a mix of imported equipment. (Commercial terms are confidential.)
Who we build for
- Land-based RAS aquaculture: barramundi, kingfish (yellowtail), Atlantic salmon smolt, prawns, mud crab, abalone and marine live-holding systems.
- Public aquariums and oceanariums: display, holding, quarantine and life support systems (LSS).
- Aquarium and LSS integrators and consultants: fabrication partner for your hydraulic and biological design.
- Research and biosecurity facilities: universities, hatcheries and quarantine aquaculture requiring documented, repeatable equipment.
- Live seafood holding: wholesalers and processors running recirculating marine tanks.
Why Industrial Plastics
Industrial Plastics has fabricated engineered thermoplastics from its Brisbane workshop since 1971. Every job runs under an SGS audited ISO 9001:2015 quality system, with welding by DVS 2207 qualified welders and per weld traceability, standards that sit above the AS/NZS minimums. Process and project engineers review every enquiry, and every delivery carries its documentation: material certificates, weld records, inspection and test plans, and as built drawings.
The workshop at Hemmant covers 2,000 square metres with hardstand for full volume hydro testing. Local, national and international shipping is available.
Frequently asked questions
None in principle. Protein skimmer is the common aquarium term and foam fractionator or protein fractionator is the term used in aquaculture and process engineering. All describe the same process: fine bubbles lift dissolved organics into a foam that is removed. We use fractionator for the large, engineered units we build.
It removes dissolved organic carbon and fine and colloidal solids that mechanical filters and biofilters cannot capture, before they break down into ammonia and nitrate. That lowers the organic load on the biofilter, reduces turbidity and bacterial load, and adds dissolved oxygen through gas exchange.
They work best in salt water, because dissolved salts stabilise the bubbles and foam. Marine and brackish systems are the classic application. Freshwater fractionation is less efficient and needs design measures to compensate, which we can advise on.
Yes. Many operators inject ozone into the fractionator so oxidation and foam removal happen in one vessel, which improves disinfection and colour removal. Ozone-rated units need suitable materials and off-gas handling, specified at the design stage.
Typically HDPE and PVC, with clear acrylic sight glasses and stainless steel flange backing rings. We select the material for the duty, salinity and any ozone exposure, and weld to DVS standards.
From your water volume and turnover, salinity, the organic load (stocking density and feed rate), target flow per unit and whether ozone is used. Send those figures and we will size the column and the bank.
Yes. Because we design and weld in-house under one quality system, multi-unit banks come out matched and repeatable, as on the Jakarta Aquarium project.
Yes. We have fabricated and shipped fractionators internationally, including the Jakarta Aquarium supply.
Send your system details through the quote form or call 1300 465 888. We will come back to you with a sized, engineered proposal.
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