This is very simple if you do not have a dehumidifier you will be the victim of mold, fungus, and rot.
This can all be prevented by simply having ample airflow in the garden and buying a dehumidifier with a adjustable humidistat.
If you buy a dehumidifier that does not have a adjustable humidistat you will not be able to properly control the relative humidity in your garden, thus leading too problems like mold fungus and rot.
Also beware of cheap dehumidifiers on amazon that only extract 5 to 50 ounces of moisture from the air every 24 hours, these dehumidifiers will not work for indoor gardens because they simply cannot extract enough moisture from the air.
So what you want is a Dehumidifier with a adjustable humidistat that can extract at least 200 ounces of moisture from the air every 24 hours.
During the vegetative stage I recommend setting your dehumidifiers adjustable humidistat to 55% and during flower I recommend lowering this to 45% or even 40%.
If someone tells you that 70% or 90% relative humidity is good for the vegetative stage they do not know what they are talking about these relative humidity ranges are optimal only when the plant has no roots or is burly starting to develop a root system.
I hope this article helps someone prevent mold fungus and rot in their indoor garden
Peace Happy Growing