Hydroponics is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel, mineral wool, or coconut husk
The Double Flange Kit is available in 4" and 6". The kit allows you to duct to a grow tent from a window or A/C unit.