A method of growing seeds in a hydroponics apparatus to provide animal feed includes trays for receiving seeds, an environmental control arrangement for controlling a temperature and humidity of the trays, and a nutrient solution supply arrangement for providing a nutrient solution to the seeds wherein the method includes:(i) preparing the seeds by removing loose chaff, remnants of husks, and broken seeds；(ii) exposing the prepared seeds to gaseous ozone in either a) a concentration in a range of 5-10 p.p.m.v. for a period in a range of 50-60 minutes or b) a concentration in the range of 10-20 p.p.m.v. for a period in a range of 1-30 minutes, in a relative humidity range of 40%-95%, and at an ambient temperature range of 12° C.-28° C.； and(iii) growing the exposed prepared seeds to provide grown plant material for use in producing the animal feed.
