night time humidity whats too high?

hey everyone well is commin into summer time and gettin warm out where i live in BC CANADA..... and i was wondering what humidity is too high at night time? i have seen PM or white mold attack a friends indoor crop during the summer... and i dont want this to happen to me..

any advice is great thank you

HAPPY GROWING!

I like to stay bellow 80% for cutting/clones, 70% in veg and 55% in flower. Usually I dont have a problem, pretty dry here, but I have a dehumidifier just in case, I use it for drying too. Not sure what the exact danger zones are but you should be good if you stay below these. I have not had mold, knock on wood... My pops got mold without high humidity, not sure how, maybe genetics.

Does anyone know how you can acquire mold with low humidity? Maybe his gauge was malfunctioning?!?!

Maybe there is another influence we should watch for????