In this experiment, we carried out direct body size manipulation on Hydra oligactis to observe compensatory growth, and test the toxicity of the resulting hydras to Copper (II) Sulfate. We divided them into two groups, namely the Reduced and Control. The Reduced group had a body portion excised while the Control was simply cut once and put back together. Hydras were left to rejoin on a capillary needle for 1-2 hours or more if necessary. They were photographed and the size was measured with ImageJ before and after this procedure, as well as before the CuSO4 toxicity test. We also observed the morphological changes in hydra due to CuSO4 using the Wilby (1988) scale 48hrs after this test. Welch’s t-tests and a Kruskal Wallis test was carried out to asses the significance of results obtained. Our results show that Reduced hydra did undergo a decrease in body size due to grafting one day after, and half of them have undergone compensatory growth within this group. However, compensatory growth was not visible as compared to the Control group. Furthermore, when the Wilby scores from the CuSO4 toxicity test were observed, we found that both groups showed similar results in terms of toxicity. Therefore, compensatory growth was not found to have any effect on CuSO4 toxicity.