Chromium toxicity in aquatic environment may occur through industrial pollutions. The impact of its toxicity may represent health hazards for aquatic environments and public health. Therefore, Clarias gariepinus were used to investigate the chromium toxicity and assess the ameliorative effect of thyme and vitamin C. Materials and Methods: A total of 90 fish were divided into sixequal groups (n = 15). Group 1 (control negative) was fed on basal diet without chromium in water. Group 2 (control positive) was fed on basal diet with Potassium Dichromate (PD) at dose 3.6 mg LG1 dissolved in water. Group 3 was fed on diet with vitamin C at dose 200 mg kgG1 of diet without PD in water. Group 4 was fed on vitamin C diet with PD in water. Group 5 was fed on diet supplemented with Thyme extract at dose 10 g kgG1 dry food without PD in water. Group 6 was fed on thyme diet with PC in water. The experiment was done for a period of 30 days. Analyses of blood, antioxidant in tissues, micronucleus test, chromium tissue residues, comet assay and histopathology were done. Results: There was a significant decrease (p