burnt tips rust spots

Too much N will lock out calcium. Obvious signs of over feeding such as a glossy sheen on your leaves. Nothing to be done now really I wouldn’t use much ripen

Looks like you went overboard too early to on the bloom nutrients switch. I use Terra Aquita. The ratios are 1-3 meaning .3 grow to .9 bloom. Your plant has only been flowering since week 9 also. So, ripen can wait. The EC you said that came back near the feed strength. Well, if it was that high, your soil is toxic, or was. Are you watering in between every feed or just hard flushing once a week. I know it's coco, and you can feed everyday but you really don't need to. To avoid nutrient lockout in the future you can feed water or calmag water every 2nd or even 3rd feed. And get some runoff. If you are feeding you want to see at least 2/3rds that EC gone when you do the flush. So if the water is 110 ppm and your last feed was 1000 and you are getting 1000 or even more you are in nutrient lock. If she's giving back 3-500 ppm take away the water feed (110) from the flush run off to get how much she's eating. If it's giving back half the EC strength you can either lower the feed or do as I said and water in between or every 3rd feed and make 1 of those feeds once a week with calmag.

The burnt tips and the curled leaves are usually a sign that you had a bit too much nutes going at one point of the grow. Not a big deal I really wouldnt worry about it especially in week 7. The plants look great . If you had real nitrogen toxicity you would have a very dark green almost blue shiny leaves, but you didnt quite get there so your good. I would just watch to not over do anymore nutes but your good! Lots of frost on those gonne be good smoke!

Looks like your plants need Cal/mag, a higher dose 4sure.

maybe those concentration where a bit too much for the plant. i would suggest to start a flush now ( bring it as low as possible) e after 3-4 days give ripen and see how it goes. the ideal pH is a bit more on the neutral side during flowering , 6,3 - 6,5 the best. Anyway if the plant has been suffering at those EC i would consider to lower the EC of ripen to 1.4 ms/cm and water pH of 6,8. You're almost there.