Fig. 1. Measured levels of total water (A) and plasma (B) [ammonia] in the 0 (N=10), 500 (N=10), 750 (N=10) and 1000 (N=10-12) µmol l^-1 NH₄Cl treatments after 24 or 96 h exposure periods. Values are means + 1 S.E.M. Treatments that do not share a common letter for a given time are significantly different from each other. ^*Significant differences between exposure periods for a given treatment (P<0.05).