Help, tops of bud/pistils looking brown and singed

[A4]

I would go ahead and be adding the calmag and water at 6.8. You said earlier that you watered @ 6.2 with runoff @ 6.3. That makes your soil ~ 6.4. If you water this time @ 6.8 that should put your soil right about 6.6. One the next water or feeding, shoot for 6.6 and read runoff again. You should be right in the sweet spot at that point. Best of luck!