well, noone is answering this one, so i'll go ahead, and no i don't have the answer, in fact i wanted to know it, too.
all i can say is having grown up in a spanish speaking country that i can't think of an equivalent, not even close, other than:
no pierdas el tiempo, or dejate de perder el tiempo.( don't waste your time, or stop wasting your time)
el tiempo es dinero (time is money)
el tiempo vuela (time flies), all of which you probably already know as they are all elementary spanish. te aviso si encuentro la respuesta, que te parece?