What the Science Says About Light, Growth & Salmon

Lighting in aquaculture is a science-backed lever for performance.

Here at HATO, we’ve built our approach around the studies, field trials, and biological mechanisms that show what light can really do for salmon growth and welfare. 

Here’s what the science tells us and why it matters to your operation. 

Study 1: Continuous light improves growth 

In a 2010 study (Leclercq et al.), salmon exposed to long light durations (LL) grew significantly faster than those under traditional photoperiods. Fish under longer photoperiods showed >10% increase in harvest weight. 

Why it matters:

A well-timed light schedule accelerates growth and feed conversion without stressing the fish. 

Study 2: Pineal response & hormonal balance 

The pineal gland in salmon regulates hormonal rhythms, including those related to maturation. Under the right intensity (≥ 0.016 W/m2), light suppresses melatonin, delaying maturation and extending the growth window. 

• Early maturation dropped to nearly 0% 
• Sexual development was suppressed in critical smolt phases 

Why it matters:

Lighting becomes a non-invasive way to extend productivity and maintain fish quality longer. 

Study 3: Feed Efficiency Goes Up  

Salmon under optimized lighting (especially in the blue-green range) not only ate better—they used the feed more efficiently. 

• FCR improved  close to 10% in commercial trials 

• Less feed needed to reach the same (or better) growth levels

Why it matters:

Feed is your biggest cost. Lighting improves ROI without changing your nutrition strategy. 

In Conclusion  

Science has made it clear: light affects salmon on a biochemical, behavioral, and financial level. At HATO Aqua, we’ve translated these findings into purpose-built lighting systems that are easy to use and proven to perform.