uuummmmm, absolutely no flushing in my organics/soil for sure....whens the last time anybody flushed outside??? i'm also running chems in hydro, i haven't flushed those either....it burns to gray ash. it's tasty as hell. as i have said many times before....chems get a bad reputation for bein "poison"...yes, if you drink em. but, after the plants use the nutes and they are converted into mass, quite simply...nutes become YOUR PLANT. essentially the plant "is" nutes. the building blocks within all plant cells have been formed, and are solid mass, i don't believe "flushing" can actually cause the plant tp "purge" unwanted nutes in any way. my thought on flushing may not be the same as everybody else's....but why are the roots there....to feed, and filter???? ummmm yes!