Fig. 5. Plasma concentrations of (A) chloride (Cl^–, solid line), sodium (Na⁺, dashed line), (B) potassium (K⁺, solid line), calcium (Ca²⁺, dashed line) and magnesium (Mg²⁺, dotted line), over the duration of the experiment when fish were allowed to feed voluntarily on a 1% of body mass ration. Values are means ± s.e.m. (N=8).