ULNS and fish color

[solitude127]

Does having a ULNS affect the color of fish? Do fish need some sort of nitrate or po4 for coloring? We've seen/read what this does for corals, but is there an affect on fish?

 

[seapug]

Fish in ULNS are typically healthier and more colorful for the same reason as corals are-- they are in pollutant free water and can be fed more often with richer foods with less fear of nitrate/phosphate buildup. In fact, there are many Tangs and Angel fish species that are very sensitive to high nitrate levels.