Yellowing leaves

Ill chalk this down to multiple fuckups. Thanks for the help!

Mag. Either not enough mag in coco, or overwatering impeding uptake.... or possibly both. Calmag weeks up to 4-5 in flower, magsulfur there after.

oh and your in flower you should be cutting most nitrogen out of the plants diet, your plant will lose leaves due to lack of nitrogen, leaves will turn yellow and die off due to lack of nitrogen. focus on feeding your buds and keeping and eye on those trichomes

ph. your ph is off, flush your plant with just water until you get a run off ph 6. let your pots dry a bit before you feed, also you should pick up some kelp and use it in you feed, it will help your plant bounce back from the shock to her system. take care of the ph issue very first thing, when your ph is off your plant does nt eat the way it should, keeping your ph in line you will see happy healthy growth and a big yield

You are right, most likely Nitrogen deficiency. Be careful if you decide to use coffee grounds, as coffee is usually pretty acidic and can throw off your pH of the soil and cause even more issues with nutrient lockout.