Flow-through, acute (96-h), and early life stage (28-d after hatch) toxicity tests were performed with eight chemical on a saltwater fish, sheepshead minnows (Cyprinodon variegatus). Chemical effects on survival, growth, and development were determined. Maximum acceptable toxicant concentrations (MATCs) were greater than 3.2 less than 7.7 mg/l for toluene, greater than 0.52 greater than 0.97 mg/l for acenaphthene, greater than 80 less than 156 mg/l for isophorone, greater than 10 less than 16 mg/l for 4-nitrophenol, greater than 4.8 less than 8.5 mg/l for bromoform, greater than 0.39 less than 0.79 mg/l for 1-chloronaphthalene, greater than 0.09 less than 0.18 mg/l for 1, 2, 4, 5-tetrachlorobenzene, and less than 0.36 mg/l for 2, 4-dichloro-6-methylphenol; application factors were 0.25-0.59, 0.17-0.31, greater than or equal to 0.57, 0.31-0.50, greater than or equal to 0.68, greater than or equal to 0.56, 0.27-0.54, and less than 0.10. respectively. Test results reported here were compared with results of static, acute toxicity tests conducted previously with six species of aquatic organisms and the same chemicals.