Effect of pH and salinity on growth and bloom of Dunaliella sp. algae

In this study, effects of pH and salinity on growth and bloom of Dunaliella sp. algae were investigated. The algae were reared in different pH (6.0, 6.8, 7.0, 7.3, 7.6, 8.0, 8.6, 9.0, 9.7 and 11.0) and salinities (20.0, 31.6, 50.1, 79.4, 117.1, 125.9 and 200.0 ppt) at Inland Aquaculture Research Institute Phycolab during 2011. After 96 h, the algae reared in 50ppt salinity and below that had negative growth, however, beyond the 50 ppt, it started to grow and reached the growth peak in 117.1 ppt. In 125 and 200 ppt, the algae growth decreased compared to 117.1 ppt. Exceptsalinityof31.62and50.11descendant of the other groups was significant (P < 0.05). At the different pH, after 96 h the lowest growth was observed in pH 11, whereas, the highest growth was in pH 7.6 while increasing pH above 9.0 led to negative growth. These differences were significant (P <0.05).