20mm Metric Union Coupling
SKU: PVC-UNCPLG-20
- Rapid Disconnect: Allows for the quick, tool-free removal of 20mm metric plumbing sections for cleaning, maintenance, or reconfiguration.
- Precision Metric Fit: Sized specifically for 20mm metric PVC pipe (approx. 0.78" OD), the standard for Reef Octopus skimmer feeds and reactor plumbing.
- Reliable O-Ring Seal: Features a high-quality rubber O-ring that provides a 100% water-tight seal without the need for Teflon tape.
- Industrial UPVC: Constructed from thick-walled, high-impact grey UPVC for superior durability compared to standard white PVC.
- Maintenance Essential: Ideal for installing near pumps or reactors where periodic removal for cleaning is required.
- Corrosion Proof: 100% saltwater safe; engineered for permanent use in high-humidity sump environments.
Reef Octopus
Globally trusted for premium protein skimmers and pumps, engineered in-house for unmatched reef filtration performance.
20mm Metric Union Coupling
The 20mm Metric Union Coupling is a professional-grade plumbing component designed to bring modularity and serviceability to your aquarium’s life support system. Precision-molded for 20mm Metric PVC pipe, this union provides a secure, high-pressure connection that can be easily unscrewed by hand, eliminating the need to cut pipes when performing routine maintenance.
In high-end reef systems, 20mm lines are frequently used for media reactor feeds, small return branches, and internal protein skimmer plumbing. By installing a union in these runs, you can easily remove equipment for deep cleaning or part replacement. The fitting consists of two socket tailpieces, a threaded collar, and a precision-seated O-ring that ensures a leak-proof seal even under the constant vibration of aquarium pumps. Its industrial grey finish ensures a professional aesthetic that matches factory Reef Octopus hardware.
Key Features
True Metric Calibration: Fits 20mm OD metric pipe—essential for maintaining factory Reef Octopus and European-spec filtration.
Simple Maintenance: The threaded collar allows you to break the connection in seconds without tools.
Bubble-Tight Seal: The internal O-ring compensates for minor misalignments and prevents leaks.
Marine-Grade Material: 100% non-metallic construction; will not rust or leach harmful chemicals into the water column.
Compact Footprint: Engineered to provide a robust disconnect point without taking up excessive space in tight cabinets.
Ideal For
Reactor Feed Lines: Allowing for the easy removal of GFO, Carbon, or Calcium reactors.
Pump Connections: Installing on the discharge of small return pumps for effortless cleaning.
Modular Manifolds: Creating removable branches in a 20mm manifold system.
What’s Included:
(1) 20mm Metric Union Coupling (2 Tailpieces, 1 Collar, 1 O-Ring)
Specifications:
Size: 20mm
Connection Type: Slip x Slip (Socket) with Threaded Disconnect
Material: Industrial Grade Grey UPVC
Seal Material: High-Grade Rubber O-Ring
Compatibility: 20mm Metric Pipe ONLY
- Ensure both 20mm metric pipe ends are cut square and deburred.
- Crucial Step: Disassemble the union and slide the threaded collar onto one pipe end before gluing the tailpiece.
- Clean the pipe ends and the internal sockets of the tailpieces with PVC cleaner.
- Apply PVC primer and solvent cement to both the pipe and the tailpiece sockets.
- Push the tailpieces onto the pipes and allow them to cure fully (approx. 1 hour).
- Ensure the O-ring is seated cleanly in its groove.
- Align the two tailpieces and screw the collar onto the threads by hand until firm.
Pro Tips:
- Check Your Sizing. A 20mm metric union will not fit 1/2" or 3/4" USA standard pipe. 20mm is a specific metric outer diameter (approx. 0.78 inches). Always confirm your pipe diameter before solvent welding.
- O-Ring Care. To ensure the union remains easy to open after months of saltwater exposure, apply a tiny amount of food-grade silicone grease to the O-ring during installation. This keeps the rubber supple and prevents "salt creep" from seizing the threads.
- Don't Over-Tighten. Unions are designed to be hand-tightened. Using pliers or a wrench can crack the UPVC collar or pinch the O-ring, which actually increases the likelihood of a leak. If it leaks when hand-tight, check the O-ring for debris.