An anesthetic and therapeutic composition for use in aquaculture includes an essential oil preferably thyme oil that is mixed with ethanol in an amount of one part essential oil preferably thyme oil to five parts ethanol. The essential oil ethanol mixture is then dispersed in water preferably seawater to provide 10 to 60 ppm of essential oil. The oxygen in the composition is between about 5.00 and 6.5 mg/L and in a preferred embodiment is enhanced by an agar stabilizer. The invention also contemplates treating fish such as sheam and sobaity and shrimp and seahorse to reduce stress and maintain a temperature of about 20°-27° C.
