Red Sea Reefer 250 G3 - Black Cabinet

The Red Sea Reefer 250 G3 - Black Cabinet is a premium 245 L / 64.7 gal reef-ready aquarium and cabinet system for aquarists who want a larger rimless REEFER G3 display with a black marine-spec stand and professional sump-based filtration layout.

As the 90 cm model in the compact rimless REEFER G3 lineup, the REEFER 250 G3 gives hobbyists a broader reef canvas with more horizontal swimming room, more coral placement space, and a stronger visual presence than the smaller 170 and 200 systems. It includes a rimless ultra-clear glass aquarium, black marine-spec plywood cabinet, REEF-SPEC sump, ReefMat-ready mechanical filtration section, ReefGate precision flow valve, central surface-skimming overflow, curved dual return nozzles, pre-assembled plumbing, and integrated ReefATO+ smart top-off control.

Red Sea REEFER 250 G3 Black Reef System

• 90 cm reef-ready platform: The REEFER 250 G3 provides a longer 90 cm display for more natural aquascaping, better fish movement, and broader coral layouts.
• 245 L total system volume: The added volume supports greater stability and more reef planning flexibility than smaller compact systems.
• Black cabinet finish: The black marine-spec plywood cabinet gives the system a clean, high-contrast look that suits modern reef displays.
• Base REEFER flexibility: Lighting, return pump, skimmer, heater, wavemakers, and advanced equipment are selected separately so the build can match the customer’s reef goals.
• Rimless display style: The 250 remains a rimless ultra-clear model, giving it a clean modern appearance without bulky top bracing.
• Strong custom reef foundation: The system is ideal for aquarists who want more than a nano reef but still prefer a controlled, elegant, cabinet-and-sump package.

Longer Ultra-Clear Display and Reef Layout Space

• 203 L / 53.6 gal display: The display gives more space for coral colonies, carefully selected reef fish, and a more open aquascape.
• 90 cm length: The longer footprint supports island reefs, sloped rockwork, open channels, swimming lanes, and multiple coral zones.
• 12 mm glass specification: Red Sea lists the 250 G3 with 12 mm front, side, and bottom glass for this rimless model.
• Ultra-clear viewing: Low-iron glass improves visual clarity and helps coral colours look cleaner through the panels.
• Marine-spec cabinet: The black plywood cabinet is designed to support the aquarium and sump while maintaining a clean furniture-style installation.
• Display-centered design: The sump and equipment live inside the cabinet so the visible tank stays clean and reef-focused.

G3 Flow System and Quiet Drain Control

• Improved circulation architecture: The REEFER G3 flow system uses redesigned water management for stronger circulation and better efficiency.
• Silent downflow system: The enlarged rectangular inlet helps reduce turbulence for quieter operation.
• ReefGate precision tuning: The high-precision gate valve gives fine drain-line control so the system can be adjusted for smooth sump operation.
• Surface skimming overflow: The central overflow pulls water from the surface to help remove film and floating debris.
• Curved dual returns: The improved return outlets help spread flow back into the display more effectively.
• Ready-to-assemble plumbing: Included plumbing keeps installation cleaner and avoids the uncertainty of building a custom overflow system from scratch.

REEF-SPEC Sump and ReefATO+ Automation

• 42 L sump volume: The in-cabinet sump provides dedicated filtration and equipment space below the display.
• Mechanical filtration included: Micron socks and media cups are included for immediate mechanical and media filtration options.
• ReefMat-ready layout: The sump’s mechanical chamber is prepared for optional Red Sea ReefMat automatic fleece-roll filtration.
• Integrated ReefATO+: The smart top-off system helps maintain stable water level and salinity while also providing temperature monitoring and leak detection.
• Advanced equipment potential: The sump can support skimming, reactors, dosing lines, probes, media, and optional Red Sea smart devices.
• Long-term reef foundation: The 250 G3 gives hobbyists enough space to grow into more advanced filtration and automation without replacing the tank.

Red Sea Reefer 250 G3 Black Specifications

• Total system volume: 245 L / 64.7 gal.
• Display volume: 203 L / 53.6 gal.
• Sump volume: 42 L / 11.1 gal.
• Display dimensions: 90 cm L x 50 cm W x 53 cm H / approx. 35.4 x 19.7 x 20.9 in.
• Total height with cabinet: 140 cm / approx. 55.1 in.
• Glass thickness: 12 mm front glass, 12 mm side glass, 12 mm bottom glass.
• Display format: Rimless ultra-clear glass aquarium.
• Cabinet: Black marine-spec plywood cabinet with leveling feet.
• Filtration: REEF-SPEC sump with mechanical chamber, micron socks, media cups, ReefMat-ready layout, and ReefATO+.
• Recommended return pump: Red Sea ReefRun G2 6000, sold separately.
• Recommended lighting: Red Sea ReefLED G2 115, sold separately.

Application Notes for the REEFER 250 G3

• Best use: Ideal for saltwater reef aquariums, LPS reefs, soft coral systems, mixed reefs, and more substantial custom reef builds.
• Longer aquascape advantage: The 90 cm length gives better room for fish movement and coral spacing than shorter compact systems.
• Equipment planning: Select an appropriate return pump, skimmer, lighting, heater, and flow system before filling and cycling.
• ReefMat upgrade option: The ReefMat-ready sump is useful for aquarists who want lower-maintenance mechanical filtration.
• Lighting selection: The recommended ReefLED G2 115 is sold separately, and other suitable reef lights may be chosen depending on the build.
• Not included: Lighting, return pump, protein skimmer, heater, wavemakers, livestock, rock, sand, salt, optional ReefMat, dosing equipment, and test kits are sold separately unless otherwise stated.

Red Sea REEFER G3 Series Video

Setup and Installation Notes

• Assemble the cabinet first: Build and level the black cabinet according to Red Sea’s instructions before placing the aquarium.
• Plan equipment before setup: Choose return pump, skimmer, lighting, heater, and wavemakers before cycling the tank.
• Install plumbing carefully: Confirm the overflow, downflow, ReefGate valve, return plumbing, sump, and ReefATO+ are installed correctly.
• Leak test with freshwater: Test plumbing and sump operation before adding saltwater, rock, or livestock.
• Tune the drain system: Use small ReefGate adjustments to reach a quiet, stable sump water level.
• Use RO/DI water: RO/DI water is recommended for mixing saltwater and topping off evaporation.
• Cycle before livestock: Establish stable biological filtration before adding fish or corals.

What’s Included

• Ultra-clear rimless glass aquarium
• Black marine-spec plywood cabinet with leveling feet
• REEF-SPEC sump with mechanical chamber, micron socks, and media cups
• Pre-assembled downflow and return plumbing with ReefGate precision valve
• Central overflow with removable surface skimmer
• Curved dual return nozzles
• Integrated ReefATO+ sensors and controller

Shipping Notes

• This item is exempt from our free shipping policy.
• To avoid delays, please order Red Sea aquariums by themselves. If you are wishing to order multiple things, please place two separate orders: one for the aquarium and one for the rest of your products.
• Please call for a shipping quote if ordering from NWT, YK, or NUN.
• All Red Sea aquariums are brought in and shipped out on an as-ordered basis. The average turn-around time to ship an aquarium to you is two business days, except where noted below.
• All shipments outside of the Vancouver area are shipped via trucking company with residential and power tailgate delivery, and are fully insured.
• Tanks ordered within BC and, in some circumstances, Alberta may take an extra 5-10 business days to process. Systems ordered from Alberta and east of there usually ship within two business days direct from the distributor in Ontario.
• If you are ordering for pick-up from our store, please select in-store pickup to avoid delivery charges. You will be notified when the tank arrives, usually within 5-10 business days.
• Red Sea Max S Series aquariums are always special order and will take from 3-6 weeks to ship.
• Please note the freight company is only responsible for getting the aquarium to the destination address and off-loading it. They are not responsible for carrying it inside.
• All freight charges have been greatly subsidized to help you get up and running with your new Red Sea system.