puzzled any input would help!!

Soil - FF Happy Frog
CalMag - 6ml
Bloom - dyna grow 4ml
RO water



any idea what this might be or cause of it???

1 week flowering... last watering was 1ml of FF grow big 2ml of Bloom and 5ml of CalMg

Do you feed every watering? Looks like nute burn.

I agree with RL 420 the leaf looks leathery and a lil burnt both signs of over nuting. give it a good flush and check the ppm of the runoff.

yep cut back on your nutes a bit! rule of thumb when going into flowering and feeding for the first time, always start out at half the recommended dose for your plants because every strain is different on how it reacts to feeding and its much easier to add a little more ferts next time you water then trying to fix a nute burn issue!

that leaf was still photosynthesizing energy for your buds when you pulled it off