Green Killing Machine 24W — Internal UV Sterilizer 120 Gal Zigzag Flow Fresh & Saltwater - Aqua-Fit

The Green Killing Machine (GKM) 24W by Aqua-Fit by AA Aquarium is the most powerful internal UV-C sterilizer in the GKM range, designed for freshwater and saltwater aquariums up to 120 gallons (450 liters). All-in-one system with built-in 120 GPH pump, sealed 24-watt UV bulb, control box, and adapter—5-minute installation with no tools or plumbing required.

Benefits of the Green Killing Machine 24W

• 24-watt UV-C radiation at 254 nm: maximum power to eliminate suspended algae, bacteria, yeasts, molds, and pathogens
• Patented Zigzag Flow design inside the casing to maximize UV light exposure time
• Integrated 120 GPH (430 L/h) pump with reduced flow in the bulb (70 GPH) for effective sterilization
• Helps combat cyanobacteria, dinoflagellates, ich, and velvet in both freshwater and saltwater
• 12V DC ChildSafe power supply—safe for fish, plants, and invertebrates
• Indicator LED on the control box signals when to replace the UV bulb
• Bonus filter sponge included
• UL, cUL, and GS certified by TÜV—the only internal UV sterilizer certified by Underwriters Laboratories

Installation and use

The GKM 24W attaches inside the aquarium with suction cups and can be positioned vertically, horizontally, or in a filtration sump. Assembled dimensions: 4" x 4" x 17". The control box must remain outside the aquarium. For optimal results, let it run 24/7 for the first 2 weeks, then connect to a timer (8 hours per day) to extend bulb life. Do not use simultaneously with medication—UV neutralizes chemical treatments.

Technical specifications

• UV-C power: 24 watts at 254 nm
• Power supply: 12V DC
• Pump flow: 120 GPH / 430 L/h (flow in the bulb: 70 GPH)
• Capacity: aquariums up to 120 gallons (450 liters)
• Compatibility: freshwater and saltwater
• Assembled dimensions: 4" x 4" x 17"
• Double Pin Connector
• Bulb life: 6 to 9 months (continuous use)
• Included: 120 GPH submersible pump, sealed UV bulb, control box, DC adapter, filter sponge + bonus sponge, suction cups
• Warranty: 1 year against material and manufacturing defects (UV-C bulb excluded)
• Certifications: UL, cUL, GS (TÜV) — EPA Est. #093568

Available formats — Green Killing Machine

• Mini GKM 3W — aquariums up to 20 gal (80 L)
• GKM 9W — aquariums up to 50 gal (200 L)
• GKM 24W — aquariums up to 120 gal (450 L)

Why choose this product from ReefSolution

The Green Killing Machine 24W is the most powerful internal UV solution for large aquariums and reef systems with sumps. Complete your setup with the Green Killing Machine 9W for a secondary aquarium, Seachem Purigen for organic chemical filtration, or Seachem Clarity to quickly eliminate residual turbidity.

Frequently asked questions

Can the Green Killing Machine 24W eliminate ich and parasites in aquariums?

The GKM 24W helps reduce waterborne pathogens, including the free-swimming stages of ich (Ichthyophthirius). For complete parasite treatment, it should run 24/7 in addition to fish observation and quarantine protocols.

Can the Green Killing Machine 24W be placed in a reef sump?

Yes, the GKM 24W can be positioned vertically, horizontally, or directly in a sump. This is the recommended installation method for reef aquariums to keep the display clean.

What is the difference between the Green Killing Machine 9W and 24W?

The GKM 9W treats up to 50 gallons with a 50 GPH pump. The GKM 24W treats up to 120 gallons with a 120 GPH pump and an internal flow rate of 70 GPH for faster sterilization of larger water volumes.