I don't think the hydro coals would be a place for rot because they have all that fresh air flowing through them. The soil DOES have a drain (into the hydrocoals) and the hydrocoals allow for a good passage of air.
Buddahbear Reviewed by Buddahbear on . Soil bed idea. After reading a thread on organic soil beds (and reading Organic Marijuana Soma Style) I've decided to grow organic with a soil bed. "They are made out of wood lined with black waterproof plastic. The bottom 5 centimeters is made up of hydrocorals, little round clay pebbles, covered by a piece of plastic coated chicken wire. On top of the chicken wire I place, some felt root cloth, then 25 centimeters of organic soil mixed with perlite. In each corner of the bed I have a 70 MM PVC pipe 35 Rating: 5