*6.1.2.2 Evaluation of water physicochemical parameters*

The physicochemical parameters recorded in the two larval rearing tanks are relatively similar. The figure below (**Figure 5**) shows the variation of these parameters during 24 hours.

During larval rearing, the recorded temperature varied between 27.5 and 30.38 (average 28.84) during May and June 2017, respectively. To highlight the prior effect of abiotic factors on larval growth during larval rearing, statistical tests performed showed that temperature, followed by dissolved oxygen, control largely larval growth. We reported a decrease in oxygen level during the first hours of the day, which led us to install 1.5 hp. aerators to improve the performance of this parameter. On the other hand, salinity and pH seem to have a non-significant effect on larval growth.
