humidity levels too high

I currently have a dehumidifier that is tio2 and uv to remove humidity and damprid and made rock salt dehumidifiers as well. I keep reading that humidity levels over 40 is bad for plants in flower. I have just now induced my lovely ladies into flower and do not want to see bud rot. I am scared of that happening. I have figured out what my ladies like for nutes and have that down. My question is: if I use a product like serenade fungicide on my buds, if and only if they do get any form of botrytis and spray than harvest, will the buds make me sick if I smoke or eat edibles from the fungicide? I read that serenade can be sprayed on, dried and afterwards you can eat what you have sprayed. I need validation on this before I make a decision to buy this spray. I plan on getting everything from my ladies with no waste. Anyway I have the humidity level to 55 percent. I want to know how to lower it more. Will a carbon filter/fan setup do the trick? I haven't purchased yet, cause I live in a spot where I don't have to worry about smell. Any solid advice will be greatly appreciated.

55% isn't bad that's pretty good actually. my skunk #1's are 5 weeks in flower and my rh is sometimes above 70% and i havent gotten any rot, i just got my dehumidifier today, about to install it. just move alot of air around with fans and you'll be okay, air flow is key. extraction fans might help you but I think you're fine. is your strain sativa or indica?

45 to 55 is fine

My strains are blueberry kush, mostly indica and hardy girls too.

I think you'll be fine as long as you have good airflow. what kind of dehumidifier do you have? I'm trying to figure out the timer on mine to just work at lights off.

Im fixing humidity problem with one lamp which makes heat. If usually i got 65°/. Than after turning on lamp it drops lower than 45. Make good airflow and it will be ok.