Your doing Great, nice looking plant...
The leafs are turning because the plant is draining there stored nutes in them for food as your not feeding it, a good thing...
The bigger buds will always have some white hairs at the top because it's new growth, if the hairs are orange on 70/80% of the entire big bud your almost if not there...
The PH is dropping because of the salt/nute build up in the medium and the water is flushing them out, also a good thing...
The leafs are turning because the plant is draining there stored nutes in them for food as your not feeding it, a good thing...
The bigger buds will always have some white hairs at the top because it's new growth, if the hairs are orange on 70/80% of the entire big bud your almost if not there...
The PH is dropping because of the salt/nute build up in the medium and the water is flushing them out, also a good thing...