Yellowing/rust spots starting from the top, kalichakra 1 month into flowering, HELP!

I'm growing in FFOF I have them are under a 400w light and are about 1 month into flowering. The strain is kalichakra from mandala. There in 3 gallon grow bags, the light is about 8-10" from the tops. Temps are around 75-78.

I fed them with half strength grow big, tiger bloom and cal-mag about 5 days ago, and this problem started about 2 days ago getting worse every day. Before that feeding there were no problems. Is this nute burn? It's starting mostly from the second node, then moves down. I'm going to be doing a small flush tonight to see if that will help. Any other ideas? Any help would be great thanks!

ya theyre burnt. hit em with some fresh and hope for the best.

Ya bro, I would do a good flush, she still looks good just get her cleaned out. I have a flowering plant that I have to always use week nutes for some reason or it freaks out. There like us man... sensitive lol

See i dont know to me that resembles more of a deffenciey...beacause im most chemical burn ...from my own experience...the leave curl inward at the tipz and get crispy....plus where the leaves get yellow generally are from lack of nitrogen but id check the nute deffecies and nuteburn section in marijuana problemz in the forum.....cross refrence thier diagnosis with youre own youll figure it out....good luck

I think it copper def .

I dont know exactly WHAT it is but i can tell you its not nute burn. If anything its a deficiency. Have you ever fed to much in the past??? Over feeding can also cause a lockup causing deficiencies. If you haven't then i would find out what you are lacking and find a way to feed it to the plant without affecting the other nutrient levels. Or it could be a ph problem. Do you have a ph meter?

Thanks for all the help guys. I did flush them last night so we'll see what happens. I don't have a digital pH meter but I do have a liquid one, it's not perfectly accurate so I plan on buying a digital one soon. It could be a pH issue since my tap water is a good pH without having to adjust it but I do usually have problems when I'm giving nutes since I have to adjust the pH. So I'm assuming it's lock out because of the bad pH from the nutes, I'll continue to flush and go out and get me a real pH meter. Thanks guys