lighting

Kelvin

Color temperature unit

What does Kelvin mean?

Kelvin (K) measures the color temperature of a light source. Higher K = bluer; lower K = warmer/yellower. Reef LEDs typically run 14,000-22,000K (blue-heavy spectrum where coral fluoresces).

How is Kelvin used in aquariums?

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.

Browse the full glossary for more aquarium terms.

Frequently asked questions

What does Kelvin mean in fishkeeping?

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