Mold risk begins at about 45% humidity (it's rare to see mold at that %RH though! You have to be screwing something else up pretty seriously) depending on a couple other factors:
-bud density- fluffy buds= less risk
-strain's natural resistance to pathogens
-plant's immune system health (potassium and silica are important)
-air flow- more flow= less stagnation= less risk
-difference between night and day temps- Minimizing temperature swing between night and day will decrease your mold risk and allow you to run a higher %RH because you won't get dewfall.
Generally, keeping your flower room under 50% with all other conditions being reasonable you should never see mold in your buds.
I don't know about how young you can go using cannazyme. HAve you tried peroxide treatment yet?
Finally, consider something like SubCulture innoculant (just looked it up and it's listed interchangeably with hydroguard)... here's a link to some basic considerations for use:
Beneficial Bacteria Explained | BGHydro

Would you like me to clean up this thread a bit?