I’ve had our Victorian terrace basement tanked, re-plastered and repainted to use as an office/occasional guest room. It doesn’t have a window that opens and generally it still smells a bit musty. I’ve got a trickle fan on the ceiling and a Meaco dehumidifier down there that needs emptying every 2-3 days. Is there anything else I can do? I’ve added a few big houseplants that like this kind of dark room already.