Red Sea Reefer 425 G3+ - Black Cabinet

Red Sea Reefer 425 G3+ - Black Cabinet

The Red Sea Reefer 425 G3+ - Black Cabinet is a 433 litre (114.4 US gallon) reef-ready aquarium system combining a 343 litre (90.6 gallon) eurobraced ultra-clear glass display, a 90 litre (23.8 gallon) REEF-SPEC filtration sump, a reinforced black marine-spec cabinet, and integrated ReefControl Pro automation. Its 120 cm (47.2 inch) length and 60 cm (23.6 inch) front-to-back depth provide substantial space for coral colonies, open swimming channels, and multi-level reef structures.

The REEFER 425 G3+ brings Red Sea's larger-system features into a four-foot reef aquarium, including 15 mm perimeter eurobracing, dual curved return outlets, precision ReefGate flow control, and the ReefControl Pro Controller with ReefControl ATO Module. Its adjustable skimmer chamber, optional refugium-divider compatibility, and removable ReefMat-ready filtration compartment provide flexibility for customized reef equipment. Lighting, return pump, protein skimmer, wavemakers, and other hardware are selected separately rather than supplied as a complete MAX equipment package.

Red Sea Reefer 425 G3+ Black Aquarium Features

• 120 cm (47.2 inch) reef display: The aquarium provides space for separated rock islands, open swimming areas, and multiple coral placement zones, making it a practical choice for customers planning a larger mixed reef or coral-focused display.
• 60 cm (23.6 inch) aquascaping depth: The front-to-back dimension allows reef structures to be arranged at different distances from the viewing glass, leaving room for coral growth, water circulation, and cleaning access.
• Eurobraced ultra-clear glass: The 12 mm (0.47 inch) front viewing panel is supported by 15 mm (0.59 inch) jet-black perimeter eurobracing and high-quality euro-silicone bonding.
• Reinforced black cabinet: The marine-spec plywood cabinet features moisture-resistant panel finishes, epoxy-painted doors, stainless steel hinges, and adjustable leveling feet.
• Floating aquarium presentation: A discreet aluminum support edge reinforces the design while maintaining Red Sea's distinctive appearance between the glass aquarium and cabinet.
• Equipment customization: The standard REEFER G3+ package supplies the aquarium infrastructure and included smart controller while allowing aquarists to select their preferred lighting, filtration, and circulation equipment.

ReefControl Pro and Integrated Automatic Top-Off

Unlike the smaller REEFER 200 and 300 G3+ models, the REEFER 425 G3+ includes the more expandable ReefControl Pro Controller. The supplied ReefControl ATO Module adds automatic freshwater replenishment and temperature monitoring, while the controller provides connections for additional compatible ReefSense probes, sensors, and controlled devices.

• ReefControl Pro Controller: Supports up to seven compatible ReefSense digital probes or sensors and two 12V DC devices, providing greater expansion capacity than ReefControl Lite.
• Automatic freshwater replenishment: The ReefControl ATO Module uses a digital water-level sensor and dedicated DC pump to replace freshwater lost through evaporation, helping maintain sump water level and salinity.
• Integrated temperature monitoring: The digital ATO level sensor incorporates a temperature sensor that provides readings, monitoring, and notifications through the controller.
• Included ATO hardware: The module provides the digital level and temperature sensor, mounting bracket, DC top-off pump, silicone tubing, tube holder, and siphon breaker.
• ReefBeat connectivity: Connected monitoring and compatible equipment can be managed through Red Sea's ReefBeat ecosystem, with historical readings, notifications, and available control settings.
• Optional monitoring expansion: ReefSense pH, salinity, ORP, and other compatible probes may be added separately. ReefControl Power can also extend the system to compatible AC equipment control.
• Base-system distinction: The ReefControl Pro Controller and ATO Module are included, but the additional ReefSense pH and temperature probe listed with MAX packages is not treated as part of this standard reef-ready configuration.

Dual Return Plumbing and Quiet ReefGate Overflow

The REEFER 425 G3+ uses Red Sea's hydrodynamically optimized water-management system, incorporating an enlarged rectangular downflow inlet, a centrally positioned surface-skimming overflow, and dual curved return outlets. The precision ReefGate valve allows the main drain to be fine-tuned to the selected return pump arrangement, helping reduce turbulence and unwanted operating noise.

• Two curved 25 mm (approximately 1 inch) return outlets: The dual connections allow filtered water to enter the display from two positions and can operate from one compatible return pump or two separate pumps.
• High-precision ReefGate valve: Small adjustments regulate the downflow rate, allowing the overflow operating level to be balanced with the return pump system.
• Enlarged rectangular drain inlet: The redesigned downflow entrance reduces turbulence as aquarium water enters the plumbing, contributing to quieter operation.
• Removable surface-skimming combs: Individual comb sections surrounding the central overflow can be removed for cleaning, helping maintain unobstructed collection of surface water.
• Hydrodynamic pipework: The factory-designed plumbing reduces unnecessary flow restrictions and supports more efficient circulation than previous plumbing configurations.
• Single- or dual-pump flexibility: The two return outlets provide configuration options not available on the smaller REEFER 200 and 300 G3+ models, which use single return connections.
• Custom plumbing connections: Red Sea offers metric and imperial connection options for aquarists planning modifications to the standard return plumbing.

90 Litre REEF-SPEC Sump and ReefMat-Ready Filtration

The REEFER 425 G3+ includes a 90 litre (23.8 US gallon) REEF-SPEC sump with removable mechanical filtration, an adjustable-height protein skimmer chamber, and support for an optional dedicated refugium. The sump provides room for compatible filtration equipment beneath the display, while the removable mechanical compartment allows an upgrade to automatic fleece filtration without redesigning the standard aquarium plumbing.

• Two 225-micron mechanical filter bags: The supplied fine-mesh bags collect suspended debris as water enters the sump and can be removed for routine cleaning.
• Two filter media cups: The mechanical filtration section includes two media cups, providing alternative filtration arrangements within the same compartment.
• ReefMat-ready compartment: The removable mechanical filtration assembly is designed to accommodate compatible Red Sea ReefMat automatic roller filtration.
• Optional ReefMat 500: Red Sea specifies the ReefMat 500 with the corresponding REEFER MAX 425 G3+ configuration, providing an identified automated filtration upgrade for the standard aquarium.
• Adjustable skimmer water depth: The skimmer chamber operating level can be set between 17 and 23 cm (6.7-9.1 inches), allowing compatible protein skimmers to operate at their intended water depth.
• Optional refugium divider: A compatible divider allows part of the sump to be configured as a dedicated refugium for customers planning additional biological filtration or nutrient-management equipment.
• Equipment separation: The sump layout keeps mechanical filtration, protein skimming, and return circulation beneath the aquarium instead of placing supporting equipment inside the main display.

Choosing Equipment for a Four-Foot Mixed Reef

The REEFER 425 G3+ provides a foundation for larger marine fish displays, soft coral and LPS reefs, and appropriately equipped mixed reef aquariums. Its deeper footprint and dual returns offer more circulation-planning flexibility than smaller REEFER systems, while the ReefControl Pro provides room for additional monitoring as the aquarium develops.

• Recommended return pump: Red Sea specifies one ReefRun G2 6000 in the corresponding MAX 425 G3+ configuration. The return pump is sold separately with this standard system.
• Reef lighting: Red Sea specifies two ReefLED G2 115 fixtures for the MAX 425 G3+ package. Other compatible lighting may be selected for the 120 x 60 cm (47.2 x 23.6 inch) footprint according to coral requirements.
• Protein skimmer selection: Red Sea pairs the MAX configuration with an RSK DC 600. Customers selecting another skimmer should verify the sump dimensions and the adjustable 17-23 cm (6.7-9.1 inch) operating depth.
• Supplementary circulation: Dedicated wavemakers can provide water movement around rock structures and coral colonies beyond the circulation supplied by the two return outlets.
• Freshwater reservoir planning: The included ReefControl ATO Module requires a suitable freshwater supply. Plan reservoir placement and tubing access when arranging equipment inside or near the cabinet.
• Optional filtration upgrades: A compatible ReefMat, refugium divider, dosing system, and additional ReefSense monitoring can be added according to the filtration requirements of the planned reef.
• 425 versus 625 G3+: The 625 offers a longer and deeper display, greater sump capacity, thicker front glass, additional bottom bracing, and front aluminum cabinet supports. Both models include ReefControl Pro and dual return outlets.

Red Sea Reefer 425 G3+ Black Specifications

• Total system volume: 433 L / approximately 114.4 US gal.
• Display aquarium volume: 343 L / approximately 90.6 US gal.
• In-cabinet sump volume: 90 L / approximately 23.8 US gal.
• Display dimensions: 120 cm L x 60 cm W x 55 cm H / approximately 47.2 x 23.6 x 21.7 inches.
• Total height including cabinet: 142 cm / approximately 55.9 inches.
• Front glass thickness: 12 mm / approximately 0.47 inches.
• Perimeter eurobracing: 15 mm / approximately 0.59 inches.
• Glass construction: Eurobraced ultra-clear glass bonded with high-quality euro-silicone.
• Cabinet: Black reinforced marine-spec plywood with moisture-resistant finishes, stainless steel hinges, and adjustable leveling feet.
• Return outlets: Two curved 25 mm connections for single- or dual-pump configurations.
• Mechanical filtration: Removable ReefMat-ready compartment with two 225-micron filter bags and two media cups.
• Skimmer chamber water depth: Adjustable from 17-23 cm / approximately 6.7-9.1 inches.
• Refugium compatibility: Optional dedicated sump divider.
• Included controller: ReefControl Pro, supporting up to seven compatible ReefSense probes or sensors and two 12V DC devices.
• Included automatic top-off: ReefControl ATO Module with digital level and temperature sensor, DC pump, and installation accessories.
• Recommended return pump: ReefRun G2 6000, sold separately.
• Optional roller filtration: ReefMat 500, sold separately.
• Manufacturer warranty: Standard 3 years, extendable to 5 years at no additional charge when registered within 90 days of purchase, subject to warranty terms.

Red Sea REEFER G3+ Series Video

Shipping Notes

• Red Sea aquariums are exempt from our free shipping policy.
• To avoid delays, please order your aquarium separately from other products. If purchasing additional items, place one order for the aquarium and a second order for your other products.
• Orders shipping to the Northwest Territories, Yukon, or Nunavut require a shipping quote. Please call for details.
• Red Sea aquariums are brought in and shipped on an as-ordered basis. The average turnaround time before shipping is approximately two business days, except where noted below.
• All shipments outside the Vancouver area are sent by trucking company with fully insured residential delivery and power tailgate service.
• Orders within British Columbia and, in some circumstances, Alberta may require an additional 5-10 business days for processing. Orders from Alberta and provinces farther east generally ship directly from the distributor in Ontario within two business days.
• For in-store pickup, select that option at checkout to avoid delivery charges. You will be notified when the aquarium arrives, usually within 5-10 business days.
• Red Sea MAX S Series aquariums are always special order and generally require 3-6 weeks before shipping.
• Freight delivery includes transporting the aquarium to the destination address and unloading it. The freight company is not responsible for carrying the aquarium inside the building.
• Freight charges have been substantially subsidized to help reduce the delivery cost of your new Red Sea aquarium.
• Rural, remote, and extended-service areas may require an additional shipping charge. We will contact you before shipping if an adjustment is necessary.

Directions

• Assemble and level the reinforced black cabinet according to Red Sea's installation instructions before positioning the eurobraced glass aquarium. Arrange sufficient lifting assistance for the aquarium and cabinet components.
• Install the REEF-SPEC sump, ReefGate valve, overflow, and supplied return plumbing, ensuring that connectors and seals are correctly positioned.
• Mount the included ReefControl Pro Controller and connect the ReefControl ATO Module, digital level and temperature sensor, and top-off pump according to the manufacturer's instructions.
• Position the ATO pump in a suitable freshwater reservoir and install the top-off tubing, holder, and siphon breaker as directed by Red Sea.
• Install the selected return pump arrangement, protein skimmer, heating, lighting, and circulation equipment before operating the aquarium. Adjust the skimmer chamber water level to the requirements of the chosen skimmer.
• Follow the manufacturer's initial-fill procedure and check the downflow and return connections for leaks.
• Adjust the ReefGate valve gradually after starting the return pump, allowing the overflow water level to stabilize between adjustments.
• Perform a power-out test to confirm the sump has sufficient spare capacity when return circulation stops.
• Clean the mechanical filtration components, removable overflow combs, return nozzles, and ATO sensor during routine maintenance.
• Register the aquarium with Red Sea within 90 days of purchase to qualify for the extended manufacturer warranty.

What's Included

• REEFER 425 G3+ eurobraced ultra-clear glass aquarium
• Black reinforced marine-spec plywood cabinet with adjustable leveling feet and stainless steel hinges
• 90 litre REEF-SPEC sump with adjustable-height skimmer chamber and removable ReefMat-ready mechanical filtration compartment
• Two 225-micron mechanical filter bags
• Two filter media cups
• Downflow and return plumbing with ReefGate precision valve
• Central overflow with removable surface-skimming combs
• Two curved 25 mm return outlets
• ReefControl Pro Controller
• ReefControl ATO Module with digital level and temperature sensor, DC top-off pump, and installation accessories