Nyos OPUS G2 250 Pro-Line Aquarium (54Gallons)

Whether you're upgrading from a smaller reef tank or building your dream saltwater aquarium from the ground up, the OPUS G2 250 combines elegant aesthetics with intelligent engineering to make reef keeping easier and more enjoyable.

Crystal Clear Viewing with Ultra-Clear Glass

Every reef deserves to be seen without compromise. The OPUS G2 250 features premium ultra-clear glass on the front and side panels to maximize light transmission and eliminate the green tint found in standard aquarium glass. Combined with transparent silicone seams and polished edges, your corals and fish become the true centerpiece of the room.

The clean, rimless pool-style construction provides a modern, minimalist appearance while allowing unobstructed viewing from multiple angles.

Hidden Overflow for a Clean, Open Display

Unlike traditional reef-ready aquariums that place an overflow box inside the display, the OPUS G2 utilizes Nyos' innovative Hidden Overflow system. The overflow is integrated behind the rear glass, preserving valuable aquascaping space while maintaining uninterrupted viewing throughout the aquarium.

Benefits include:

• More room for live rock and coral placement
• Cleaner aquascaping possibilities
• Improved water circulation
• Nearly invisible overflow design
• Modern, uncluttered appearance

Pro-Line Cabinet Offers Maximum Storage

The Pro-Line cabinet is specifically designed to provide significantly more interior storage than standard aquarium stands. The cabinet extends beyond the footprint of the aquarium, creating additional room for equipment while maintaining a sleek appearance.

Features include:

• Heavy-duty construction for long-term durability
• Push-to-open doors
• Premium soft-close European hinges
• Extra-wide interior for equipment access
• Clean cable management
• Professional furniture-quality finish

The additional cabinet depth makes installing a protein skimmer, dosing system, controller, power management, and other reef equipment far easier than in conventional aquarium stands.

Reef-Spec Sump Designed for Today's Equipment

The included glass sump is engineered specifically for modern reef filtration.

Its spacious layout accommodates today's most popular equipment including:

• Protein skimmers
• Return pumps
• Media reactors
• Auto top-off systems
• Aquarium heaters
• Filter media
• Dosing equipment

An integrated freshwater reservoir helps simplify automatic top-off operation while keeping everything neatly contained inside the cabinet.

Designed for Successful Reef Keeping

The OPUS G2 250 was created with both experienced reef keepers and ambitious beginners in mind.

Its thoughtful design provides:

• Stable water volume
• Excellent gas exchange
• Quiet operation
• Easy maintenance access
• Efficient plumbing
• Flexible equipment layout

Whether your goal is an SPS-dominated reef, vibrant LPS display, soft coral aquarium, or a stunning mixed reef ecosystem, the OPUS G2 250 provides the reliability needed for long-term success.

Premium Features

• Rimless ultra-clear low-iron glass aquarium
• Hidden rear overflow for uninterrupted viewing
• Transparent silicone seams
• Precision-engineered PVC plumbing
• Reef-ready filtration system
• Large glass sump
• Integrated freshwater top-off reservoir
• Oversized Pro-Line cabinet
• Push-to-open soft-close cabinet doors
• Modern European design
• Exceptional build quality
• Plug-and-play plumbing installation

Technical Specifications

• Display Aquarium Dimensions: 27.6" L × 21.7" W × 20.9" H (70 × 55 × 53 cm)
• Display Volume: 204 Liters (53.9 Gallons)
• Sump Volume: Approximately 42 Liters
• Freshwater Reservoir: Approximately 20 Liters
• Total System Volume: Approximately 266 Liters
• Glass Thickness: 10 mm Ultra-Clear Glass
• Cabinet Dimensions: 30.9" L × 25.8" W × 35.4" H (78.5 × 65.5 × 90 cm)
• Recommended Return Pump Flow: Up to 2,000 LPH (approximately 530 GPH)

Why Buy the Nyos OPUS G2 250 Pro-Line from Aquarium Specialty?

At Aquarium Specialty, we specialize in premium reef aquarium systems and carefully select products that meet the expectations of discerning marine hobbyists. The Nyos OPUS G2 250 Pro-Line represents one of the finest rimless reef aquarium systems available today, combining German engineering, premium materials, and thoughtful design into a complete reef-ready package.

Our experienced reef aquarium team can also help you select the ideal lighting, protein skimmer, return pump, wavemakers, controllers, and filtration equipment to build a complete, high-performance reef aquarium tailored to your goals.

Perfect For

• Reef Aquariums
• Saltwater Aquariums
• Mixed Reef Systems
• SPS Coral Aquariums
• LPS Coral Displays
• Marine Fish Aquariums
• Premium Home Aquariums
• Luxury Office Aquariums
• Serious Reef Hobbyists
• Professional Coral Displays

What's Included

Your Nyos OPUS® G2 250 Pro-Line Reef Aquarium System includes everything needed to build the foundation of a premium reef aquarium:

• Ultra-clear, rimless low-iron glass display aquarium
• Factory-installed Hidden Overflow System
• Precision PVC plumbing kit
• Glass sump filtration system
• Integrated freshwater auto top-off (ATO) reservoir
• Pro-Line premium aquarium cabinet with furniture-quality finish
• Soft-close, push-to-open cabinet doors
• Adjustable leveling feet for a stable installation
• Filter sock holder
• All necessary bulkheads and plumbing fittings
• Installation and assembly hardware
• Manufacturer's installation instructions