Hydroponics - Indoor Horticulture
Hydroponics - Indoor Horticulture represents an educational, in-depth, up-to-date, indoor horticultural growers guide that covers all principles of indoor hydroponic horticulture and gardening. This book contains 110,000 words, with over 300 diagrams, pictures, illustrations, graphs, tables, 3 dimensional CAD renderings, and is printed in full colour.
Hydroponics - Indoor Horticulture examines, explores, dissects and
presents a fully comprehensive step by step growers guide, relating
to all and every aspect of indoor hydroponic horticulture, with complete
chapters on plant biology, propagation, hydroponic systems, nutrients,
oxygen, carbon dioxide enrichment, pH, biological pest control, fungi/disease,
cuttings/clones, pruning/training, breeding, harvesting, equipment,
grow rooms, a full history of hydroponics, and more.
follows a one page sample taken from the book)
Oxygen and Water
These are the facts; warm water holds less oxygen than cold water, however, very cold water can be detrimental to the plants, effectively shocking the root system until the water warms up enough for the plants to get over this shock. On the other hand, very warm water has a detrimental effect on a plant, again shocking the plants’ roots until it cools to a level that enables the roots to recover from the shock. So, the colder and fresher the water, the more oxygen content; the warmer, the less.
Approximately 0.0014% of dissolved oxygen can be found in very cold, fresh water. Approximately 0.0008% of dissolved oxygen can be found in fresh water at room temperature and water at room temperature is exactly how the plants like it. Approximately 0.0005% of dissolved oxygen can be found in fresh water at 86°F or 30°C. So, as illustrated below, heating your water too much can be very detrimental to your plants’ potential.
Oxygen obtained via the roots directly from the nutrient solution only makes up 1% of the plants’ needs. So the oxygen supplied via the nutrient solution is only a minor source supplied to the roots. Aerating the nutrient solution will help, however, this mainly serves to kill off any pathogens, basically keeping the nutrient fresher for longer. So you can see that allowing the plants some dry time will serve to get more air to the roots. Even in aeroponics, which delivers a highly oxygenated solution directly to the rootball, it is essential to give plants dry time (at night for example), to allow air to reach the root system. Another technique is to add H2O2 to the reservoir, which again, due to its extra oxygen atom, increases the dissolved oxygen in the reservoir.