What light spectrum is best for coral growth?

Coral growth is heavily influenced by the type of light spectrum provided in aquariums. While various light spectrums can support coral health, certain wavelengths are particularly beneficial for their growth and overall well-being.

The ideal light spectrum for coral growth is found in the blue range, specifically between 400 and 500 nanometers. This range, often referred to as the "actinic" spectrum, closely mimics the natural underwater conditions where corals thrive. Blue light is essential for the photosynthetic processes of zooxanthellae, symbiotic algae that live within coral tissues. These algae convert light into energy through photosynthesis, providing the corals with vital nutrients.

In addition to blue light, corals also benefit from a balanced spectrum that includes red and violet wavelengths. Red light, between 600 and 700 nanometers, helps in the absorption of chlorophyll and enhances the overall photosynthetic efficiency. Violet light, around 420 to 440 nanometers, aids in the activation of photopigments, contributing to the corals' vibrant colors.

Aquarium lighting systems with adjustable settings allow hobbyists to recreate natural light conditions and experiment with different spectra to optimize coral growth. It's crucial to strike a balance, as excessive or insufficient light can lead to coral stress, bleaching, or even death.