Water pH and Prochilodus lineatus larvae survival.

The present study aimed to determine the influence of water pH on survival of curimbatá, Prochilodus lineatus, larvae. Forty-five 2-l glass aquaria with artificial aeration and no water exchange were stocked at a density of 10 larvae l(-1). The pH values used as treatments were 3.7 +/- 0.0, 4.0 +/- 0.0, 4.4 +/- 0.2, 4.6 +/- 0.2, 4.8 +/- 0.2, 5.1 +/- 0.2, 5.3 +/- 0.2, 5.6 +/- 0.2, 7.2 +/- 0.2, 8.7 +/- 0.4, 9.0 +/- 0.4, 9.2 +/- 0.4, 9.4 +/- 0.6, 9.7 +/- 0.5 and 10.0 +/- 0.5 in a completely random experimental design with three repetitions. Water pH was maintained by the addition of NaOH or H(2)SO(4) solutions. After 72 h of experiment, no survival was registered at pH below 4.6, 1.5% survival at pH 4.6, and about 50% survival at pH 9.4 and above. Survival rates between 70 and 80% were registered at pH 4.8-5.6 and at pH 7.2, whereas over 90% survival was registered at pH between 8.7 and 9.2.