I've got 2 Puprle Haze plants and 3 Perplex plants all female almost 3 weeks into flowering maybe already 3 but the bottom leaves on most of the plants are starting to turn yellow and I mean WAY YELLOW like solid yellow but 90% of the plant is GREEN and PURPLE AND THRIVING I'm not using enough nutes for nute burn and im talking all the way solid yellow so its not neut burn cant figure it out..any ideas??