:thumbsup:I have not yet grown a single stem all my knowledge comes from reading these forums, so please take this with a grain of salt.

You mentioned you are using MG, is it straight from the bag? I have read alot of posts suggesting adding perlite 1:4 to cut down somewhat on the nutes. Also I believe you stated you water every 3 days or so. If it were my grow I would probably transplant after sexing and after she is settled for a a couple of light cycles, keeping her good and drenched with good drainage for several days to get rid of some excess nutes in the MG. I would check the PPM of the run off and when it gets down pretty low, I would perhaps add some budding nutes.

Again, I could be totally off base here. If so please forgive my ignorance. Good luck with your grow!!