The Zoo Med Coral Sun Actinic 420 T8 Lamp (18 in) is designed to bring out the best in your reef or marine aquarium. Its strong actinic output peaks at 420nm, the wavelength range most efficiently used by zooxanthellae algae that live within photosynthetic corals and many invertebrates.

Why this lamp is ideal for your reef tank

• Optimized 420nm actinic spectrum: Output closely matches the absorption peak of chlorophyll used in photosynthesis, helping corals and clams thrive.
• Enhances coral color and fluorescence: Short-wavelength blue light makes coral pigments and fluorescent proteins stand out with vivid, glowing tones.
• Simulates natural reef-depth lighting: Recreates the blue light that penetrates deeper ocean water, providing a more realistic marine environment.
• Supports photosynthetic invertebrates: Ideal for soft corals, LPS, some SPS, and other light-loving reef inhabitants.

Energy-efficient, long-lasting T8 design

• Energy saving vs. T12 bulbs: Slim T8 format can reduce power consumption compared with older, thicker T12 lamps.
• Long service life: Effective output for up to 10,000 hours when used under normal aquarium conditions.
• European-made quality: Manufactured in Europe for consistent color, reliable performance, and stable light output over time.

Best uses

• Primary or supplemental actinic lighting on marine and reef aquariums
• Highlighting coral fluorescence in display tanks
• Combining with daylight-spectrum lamps for a balanced reef lighting system

Product details

• Type: T8 fluorescent actinic aquarium lamp
• Length: 18 inches
• Spectrum peak: 420nm (actinic blue)
• Recommended for: Marine and reef aquariums, photosynthetic corals, and invertebrates
• Quantity: 1 lamp per pack
• Origin: Made in Europe / Germany

Use the Zoo Med Coral Sun Actinic 420 T8 Lamp Blue 18" on its own for a deep-blue reef look, or pair it with a daylight bulb to create a balanced, coral-friendly lighting system that supports growth while showcasing natural colors.

Additional information