Uvc light whens best to use?

Hello gentleman i was wondering if u guys could help me out with the timeing and whens best to use uvc light 36 watt. I have an indoor grow 24 x24 x48 tent humidity is 50 _55 temp 75 to 80 shes about to go into flowering next week shes had problems wit mold i treat her with peroxide and now i wanna put in a uvc light i bought i heard helps with yield potency so im wondering my timing and i kno no direct contact kuz it can kill the plant o and its a gg4 strain in super soil a fabric 30 gall pot 600 watt led and 200 watt plant light