Red Sea REEF-SPEC Carbon 500g

Red Sea REEF-SPEC Activated Carbon — 500g is a premium, ultra-low-phosphate carbon formulated specifically for reef aquariums. It removes dissolved organics, yellowing compounds, odors, and medication residues without leaching phosphate back into your system — a common problem with lower-grade carbons. The 500g size is the sweet spot for mid-sized reef tanks.

Different size? Try the REEF-SPEC Carbon 100g or REEF-SPEC Carbon 1000g. Run it in the Red Sea Reefer Media Cup for clean, drop-in installation in a REEFER sump.

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• Reef-safe: ultra-low phosphate leaching
• Removes dissolved organics, yellowing compounds, odors, and medication residues
• Highly porous pellet structure — large active surface area
• Optimized for reef aquariums (REEF-SPEC formula)
• 500g — ideal for mid-sized reef tanks (~130 US gal)

• Use 100g per 100 L (26 US gal) of system water
• Replace every 4–6 weeks for best performance
• Rinse with fresh RO/DI water before first use
• Best run in a dedicated media bag or the Reefer Media Cup

Is it really reef-safe?
Yes — Red Sea REEF-SPEC is tested to an ultra-low phosphate leaching standard, specifically for reef use.

How do I dose the right amount?
500g treats roughly 500 L (~130 US gal). For smaller nanos use the 100g, for larger systems the 1000g.

How do I run it in a REEFER?
Load into a media bag or drop it into the Reefer Media Cup and place it in the sump's media chamber.