dehumidifier?

do i really need a dehumidifier

Guess it depends on how many plants your growing. If only one or two no, but if you have a few well yes. The humidity will raise alot during flowering and you don't want bud mold after your months of hard work.

9 plants in a 3x3x6 area

Al B says its the most important piece of equipment, really helps yield and as a side benefit you will hvae distilled water as a by product. They do make them in small sizes. VV