Fig. 2. Effects of ammonia loading (10 mmol l^–1 or 20 mmol l^–1 NH₄Cl) on (A) the NH₃ volatilization rate (µmol day^–1) and (B) the pH of the surrounding medium of Misgurnus anguillicaudatus. Open columns represent the control condition (no fish). Filled columns represent the experimental condition (with fish). Values are means + S.E.M. (N=4). *Significantly different from the corresponding control condition, P<0.05.