You really need to cut something.If you are growing in a closet,then you should really cut into the ceiling as well as the floor.With your situation,it would be safer to cut into the sheetrock ceiling and use 2 flex duct lines,one going to a freshair source.It will be easy to fix as well, versus the floor.I guess I shoulda asked ya if you were using HID or FLO's?

Ga Grown!