I think the buds look pretty awesome as well and 5 weeks into flowering your gonna get some yellowing leaves im just starting my 5th week as well and i have starting to do the same thing, im growing in soil and using Tigerbloom and it seems to be doing pretty well, one thing ive always been told not sure if its acccurate as ive never had the issue but people have told me when the stems of your fan leafs are a deep purple color its a sign of over watering, and yours look really really dark, mine always stay almost lime green a few have a little bit of purpleing to them i attached a pic of mine i went to 12/12 on Dec 10th and I think your buds are way better developed then mine but yours looks sativa dominant not sure what strain you are growing mine is a lemon Haze which is more indica, I know nothing about hydroponics so not sure if its possible or not to over water them but that is one thing id look at.