my RH often drops into the 30's as well...I was worried about it at first but now seem to live with it.
How low of a RH % would you consider to be a problem or concern?
I actually get down to low-mid 20's at times if my grow gets a bit overheated. I have a problem regulating humidity, mine might go from 22 to 60 in a 24 hour period. Your plants will let you know when it's too dry, you will see some wilting, droopiness, and maybe tip browning.
I would much prefer a low humidity problem than a high humidity problem. Low humidity the stoma close down and processes slow. High humidity stuff rots.
Indicas can handle low humidity better than sativas. Sativas can handle high humidity better than indicas. Since most good stuff today is a hybrid they are all middle ground humidity wise, in my opinion.
Low humidity to me is more of a factor in the seedling / small plant stage, when they have small root systems and are not transpiring much water into the grow area, and don't have much of a root system to uptake water. Then they can get dry. Once they get larger with a lot of root and leaf surface the plants are going to be pumping out a lot of transpired water into the grow area and then you might have to deal with high humidity.
JMHO but I am for drier air once the seedlings are soundly established.
Peace - Aim
