Sawdust as a medium for hydroponics?
Actually I have 2 questions pertaining to hydroponics. First you should know that I have a passive hydroponic system functioning right now the container is partially submerged in a nutrient solution with holes in the bottom of the container. The medium I'm using right now is perlite to allow more oxygen and act like a wick. I do have a top layer of aquarium gravel to anchor the plant better. I've been thinking of trying to add more oxygen to the roots by using an air pump. I was going to insert the tube from the top (the dry section above the water) pointing down to the wet section to blow some air to the roots. Would this be an unnecessary addition if I continue to use perlite as a medium?
My second question is the title, would sawdust work as a medium for hydroponics? I assume it would be able to act like a wick for a passive system my concern is would the roots get enough oxygen in sawdust? Also most mediums are inert sawdust wouldn't be, would that have a negative impact on my plant?