Data for "The effect of calcium on acute chloride toxicity in Daphnia species"

To assess how water hardness (as calcium) influences the toxicity of chloride (as NaCl) to Daphnia app., we conducted 48-hour acute chloride (as NaCl) toxicity tests on < 24-hour old Daphnia neonates in six calcium treatments: 1.5, 3, 15, 40, 70, and 128 mg/L (hardness ~7 to 323 mgCaCO3/L) at chloride concentrations ranging from 0.39 to 3400 mg/L. We determined the effective concentration of chloride which was lethal to 50%, 25%, and 10% of the sample populations (EC50, EC25, and EC10, respectively) from each iso-female line in each calcium treatment after 48 hours of exposure without food.