At 7% RH, I don't think I need to worry about mold. I am going to need to be raising the RH as much as I can. In my grow room right below my MJ grow, the RH is about 15% and that is with 2 bubblers, a bucket of water, and some soil plants. My point is that its hard for me to get past 40% RH even if I try (so no moisture)