The present experiment was designed to determine the effects of tricaine methanesulfonate as an anaesthetic for juvenile sailfin silver molly Poecilia latipinna at three different temperatures and anaesthetic concentrations. Silver molly (230 ± 25 mg and 24.07 ± 5.59 mm) were exposed to 150, 200, and 250 mg l-1 tricaine concentrations at 20, 25, and 30°C. Even though, a body of literature exist about the anaesthetic usage on foodfish species, not much information seems to be available on ornamentalfish aquaculture. In the experiment, three tricaine methanesulfonate concentrations for each temperature were used to anaesthetize silver molly and recorded their induction, recovery times and survival. The necessary time to make anaesthesia on fish depended on concentration intensity and water temperature rise. When exposed to any of the concentrations, fish achieved a deep state of anaesthesia with induction times of 0.18 - 1.63 min and recovered fast in 1.53 - 2.08 min. To maximize safety and reduce fish mortality and stress, the minimum concentration producing desirable anesthetic effects was 150 mg l-1 at all three temperature
