Light is one of the important and effective environmental factors in fish life that
can affect body activity and metabolism. Present study was done to study the effects
of different light colors on growth indices (Growth Rate, Specific Growth Rate and
Condition Factor), Feed Conversion Ratio and Survival Rate in tiger barb (Barbus
tetazone) juvenile for 6 weeks. To examine, 120 fish juvenile with average weight
of 0.073±0.002 g were respectively divided in to four groups treatments including
white, natural, green and blue colors (with three replicates for each treatment). Fish
were fed by Biomar commercial food twice a day. Results showed that growth
indices (GR, SGR) and FCR had significant difference in different light colors
(P˂0.05). White and green lights, respectively, led to the highest and lowest GR
and SGR in fish, however, there were similar effects of white and blue lights on
growth and also green and natural lights on growth. The best feed conversion ratio
was observed in natural light and there were no significant difference between other
treatments. In addition, the highest condition factor was related to white and blue
colors and the lowest condition factor was associated to green and natural colors.
Survival rate showed no significant difference in different treatments (P>0.05).
Results of present study showed environment light color can significantly affect
juvenile growth of tiger barb. Therefore by using suitable light color an optimum
growth could be obtained culture period.