i dont sopose any one know what is goin on whith my plants ? there 3 weeks in to there 12 on 12 .and iv started to notice a rust looking coluring on the leave and some of them are staring to curl up and die .its started at the tops mainly on the older leaves but it is now starting to move down .i have been feading them on 4.1 of sensi bloom ..could it be k def .if so how should i treat this .PLEASE HELPPPP.thanks .will post pics soon