Kelvin

Definition

Kelvin (K) measures the color temperature of a light source. Higher K = bluer; lower K = warmer/yellower.

Practical use

Reef LEDs typically run 14,000-22,000K (blue-heavy spectrum where coral fluoresces). Planted FW LEDs run 6,500-7,500K (full spectrum mimicking sunlight). Most reef LEDs let you tune K via blue + white channel mix.

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