5 weeks into flowering leaves turning brown and crisping

Hello guys, I've been growing for about a year with good results. I bloom in 15 gal. buckets, with 707 soil, 1000 watt hps, i ph every time to 6.5, i use General organics whole line, i also am trying advanced nutes on one set of plants, I've done well with G.O. I recently put in a mini split ac, i have 5 fans in room, i run co2, SInce putting in ac, the plants i put in after ac are about 5 weeks in flowering and 4 weeks in flowering , the blue cheese and ak/whitewidow, fan leaves are starting to brown and they crisp right up. They seem to be budding fine, And i'm lead to think its enviromental because its happening to my blue cheese that are on advanced nutes and i also have some on G.O. which i used for a while now and never had this problem. Was wondering if its a def. or fan burn. I can't figure it out. My humidity when lights are on is about 35%, lights off i keep a dehumidifier at 50%. its about 77 degrees in room.

Had the issue last grow. Some type of def. Mine all did that same shit. This grow I haven't had that issue. Not sure hope you figure it out.

Looks like your leaves where wet/damp and got burnt from the lamp. Are u sure that was what your humidity is or was that what your humidity was set to be at? Ac can make your top leaves burn, sudden cool air brings the moisture out then the leaves burn under the lights....the co2 increases the moisture at low temps too.
Your gonna have to raise your temps or the lights or get rid of the co2.

Your ph is too low in your soil.

Leaves curling down is ph isnt it? Curling up and folding out is heat and need for water.....

calmag and nitrogen def, dont listen to these people, the rust/yellow is calmag, and the lighter yellow is nitrogen. get calmag, and feed that along with normal range, remember leaves dont heal so it will be hard to tell the difference.