Red Sea Reefer S-850 G3

Red Sea REEFER S-850 G3 – Ultra-Premium Large Reef Display System

The Red Sea REEFER S-850 G3 is a high-end, large-format reef system engineered for advanced reef keepers who demand exceptional clarity, stability, and long-term performance. With a 224-gallon (850 L) ultra-clear rimless display and a total system water volume exceeding 280 gallons (1,060 L), including the sump, the S-850 G3 provides ample space for intricate aquascapes, large coral colonies, and high-biomass reef ecosystems.

Constructed from ultra-clear low-iron glass up to 19 mm thick, the S-850 G3 provides stunning optical clarity and a premium, modern aesthetic. Its reinforced marine-spec plywood cabinet, combined with a full internal aluminum support frame, ensures long-term structural integrity, moisture resistance, and superior load-bearing strength—ideal for permanent installations and feature reef displays.

The G3 platform features hydrodynamically optimized dual return outlets, a high-capacity overflow box, and a precision downflow valve, allowing for silent and stable operation. Its oversized REEF-SPEC sump includes mechanical filtration chambers, a large skimmer bay, refugium space, media zones, and a high-flow return section. The S-850 G3 also features the ReefATO+ system, which includes auto top-off, temperature monitoring, and leak detection for maximum stability and safety.

Whether you’re building a large mixed reef, SPS-dominant system, or a high-impact showpiece installation, the Red Sea REEFER S-850 G3 provides the scale, engineering, and performance needed for elite reef keeping.

Technical Specifications