Did you look at the color of the resin? But by the looks of it you can chop it whenever your would like.. Have you starting watering with plain water yet?
But the thing I don't understand is that "some" people will tell you to treat promix as hydro too just because there isn't any food in it. I don't know the exact range for coco but I'm pretty sure that's a ph issue that is causing nutrient lockout.
Dude it's not accurate, coco IMO is a pain in the arse.. I don't know too much about it but I see people having trouble with it all the time. I have had ph lockout before and that's what I would say is up with yours. How often are you watering?
And don't waste your money on a soil ph meter, they are inaccurate and a waste of money.. If you wanna "never worry about ph" then next time you plant some ladies add some dolomite lime to your soil and you'll never have to worry about ph again
Don't worry about your ph now, get them fed.. Thats the only problem I see, and I wouldn't recommend using the granules. If you can get some quality food in a liquid form.
Regular seeds will be more stable, the females you end up with won't have tendencies to hermi.. It's worth the little extra work to plant a few reg seeds and get your females outta them