Red Sea Reefer 300 G3 - White Cabinet

The Red Sea Reefer 300 G3 - White Cabinet is a premium 300 litre / 79.3 gallon reef-ready aquarium and cabinet system that gives aquarists a deeper 90 cm REEFER G3 display with Red Sea’s upgraded sump-based infrastructure and a bright white marine-spec cabinet.

This base REEFER G3 package is built for hobbyists who want a clean professional foundation for a custom reef aquarium while keeping full control over the final equipment selection. It includes a rimless ultra-clear glass aquarium, white marine-spec plywood cabinet, REEF-SPEC sump, ReefMat-ready mechanical filtration chamber, pre-assembled plumbing, ReefGate precision valve, central overflow with removable surface skimmer, curved dual return nozzles, and integrated ReefATO+ smart top-off control. The result is a refined reef platform ready for your preferred lighting, pump, skimmer, heater, wavemakers, and automation accessories.

Red Sea REEFER 300 G3 White Reef System

• Deep 90 cm reef platform: The 300 G3 combines a practical 90 cm display length with 57.5 cm of depth, creating a more dimensional reef canvas than narrower systems.
• 79.3 gallon total volume: The 300 L system gives more water stability and reef planning flexibility while staying in a manageable mid-size footprint.
• White cabinet finish: The white marine-spec cabinet gives the aquarium a bright, modern, furniture-style appearance for contemporary homes, offices, and display spaces.
• Custom equipment freedom: Return pump, lighting, skimmer, heater, wavemakers, dosing equipment, and controls are selected separately for a build that matches the customer’s reef goals.
• Rimless G3 display: The ultra-clear rimless aquarium keeps the look clean and modern while providing strong viewing clarity.
• Strong upgrade path: The sump and ReefATO+ platform make this system a good foundation for a Red Sea ecosystem build with future ReefMat, ReefRun, ReefLED, ReefWave, and ReefDose upgrades.

Ultra-Clear Glass with Extra Aquascaping Depth

• 246 litre display volume: The display provides room for coral colonies, open rockwork, reef-safe livestock choices, and a more mature aquascape.
• 57.5 cm display width: The added front-to-back space helps prevent the aquascape from looking flat and creates more room for ledges, caves, shelves, and open sand.
• 12 mm glass build: The REEFER 300 G3 is listed with 12 mm front, side, and bottom glass.
• Ultra-clear viewing: Low-iron glass improves clarity so fish, coral, and rockwork show with less colour distortion.
• Open-top rimless style: The braceless display provides a clean high-end look and convenient access for maintenance.
• Hidden under-cabinet equipment: The sump keeps filtration and support equipment away from the main display for a cleaner reef presentation.

Quiet G3 Downflow and Improved Returns

• Redesigned flow system: REEFER G3 systems use hydrodynamically improved plumbing designed for better water movement and efficiency.
• Low-turbulence drain: The enlarged rectangular downflow inlet helps reduce turbulence and makes the system easier to tune quietly.
• ReefGate valve: The precision gate valve gives fine control over the downflow line for near-silent operation when properly adjusted.
• Surface skimming overflow: The removable surface skimmer helps draw film and floating debris into the filtration path.
• Curved dual returns: The improved return nozzles help distribute water more evenly back into the aquarium.
• Clean plumbing package: The included pipework gives the system a factory-designed drain and return layout instead of a fully custom plumbing project.

REEF-SPEC Sump and Smart ReefATO+

• 54 litre sump: The sump gives practical space for mechanical filtration, skimmer selection, return equipment, media, dosing lines, probes, and maintenance access.
• ReefMat-ready filtration: The removable mechanical compartment includes micron socks and media cups and is designed for optional ReefMat installation.
• Integrated ReefATO+: ReefATO+ helps maintain water level and salinity stability while adding temperature monitoring and leak detection.
• Flexible filtration planning: The sump can support carbon, media reactors, refugium-style nutrient export, protein skimming, and automation accessories depending on the build.
• Service-friendly cabinet layout: Equipment is housed under the aquarium for easier access and a cleaner display.
• Built for long-term reefkeeping: The system can start as a straightforward mixed reef and grow into a more automated advanced setup over time.

Red Sea Reefer 300 G3 White Specifications

• Total system volume: 300 L / 79.3 gal.
• Display volume: 246 L / 65.0 gal.
• Sump volume: 54 L / 14.3 gal.
• Display dimensions: 90 cm L x 57.5 cm W x 55 cm H / approx. 35.4 x 22.6 x 21.7 in.
• Total height with cabinet: 142 cm / approx. 55.9 in.
• Glass thickness: 12 mm front glass, 12 mm side glass, 12 mm bottom glass.
• Display format: Rimless ultra-clear glass aquarium.
• Cabinet: White 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.
• Recommended ReefMat: Red Sea ReefMat 500, sold separately.

Application Notes for the REEFER 300 G3 White

• Best use: Designed for mid-size reef aquariums, LPS displays, soft coral systems, custom mixed reefs, and aquarists who want a deeper display footprint.
• Equipment selection: Add a suitable return pump, skimmer, lighting, heater, wavemakers, and test kits before cycling the system.
• Lighting planning: The recommended ReefLED G2 115 is sold separately, and lighting should be selected around coral type and coverage goals.
• Flow planning: Additional wavemakers should be chosen based on coral placement, rockwork density, and desired circulation pattern.
• ReefMat option: The sump is ReefMat ready for customers who want to upgrade mechanical filtration later.
• 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

• Build and level the cabinet: Assemble the white cabinet correctly and confirm it is level before installing the aquarium.
• Choose equipment before filling: Select the return pump, skimmer, heater, lighting, and flow pumps before starting the reef.
• Install plumbing and sump components: Follow Red Sea’s instructions for the overflow, ReefGate valve, drain, return plumbing, sump, and ReefATO+.
• Leak test with freshwater: Confirm plumbing, sump level, and return flow before adding saltwater, rock, or livestock.
• Tune the drain gradually: Adjust the ReefGate valve in small increments for a quiet and stable water level.
• Use RO/DI source water: RO/DI water is recommended for saltwater mixing and top-off.
• Cycle before stocking: Establish biological filtration before adding livestock, then stock gradually.

What’s Included

• Ultra-clear rimless glass aquarium
• White 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.