There is no doubt about the benefits of using hydrogen peroxide correctly in a hydroponic system. This becomes especially true if your nutrient tank is kept above 72 degrees. Hot water retains less dissolved oxygen and therefore promotes the growth of more viruses, fungi and anaerobic bacteria. Hydrogen peroxide adds oxygen to the water and cleans the water of the pathanogens. Benefits include healthier root systems, increased nutrient absorption, thicker stems and larger leaves.
One expert says it should be used on all soil gardens and in hydroponic systems. Knowing what I do about the beneficial fungi and microorganisms and the benefits they offer to living plants, I am shy about taking this advice. However, when this first line of defense fails and the plants get sick I often resort to using treatments with hydrogen peroxide on the plants grown in the soil.
The chemical formula of hydrogen peroxide is H2O2. You may notice that it is simply water with an extra oxygen atom. In fact, since hydrogen peroxide decomposes into a solution, the result is oxygen and water. Its application helps to supply oxygen to the roots of irrigated plants and helps to sterilize growing soils by killing harmful anaerobic bacteria (not compatible with oxygen) and disease-causing pathanogens. This includes bacterial wilting, pitio mushrooms, fusarium mushrooms and others.
I avoid using the common 3% hydrogen peroxide that you normally find in drug stores. This is because such low percentage solutions are unstable and chemicals are added to the peroxide to prevent them from breaking before they can be used. I did a little research because I didn’t know which chemicals were used for this, or if the plants absorbed these chemicals or if there was a health risk associated with one of these stabilizing chemicals.
Hydrogen peroxide is generally stabilized with acetanilide. Acetanilide is a synthetic compound that was first used for fever reduction and pain relieving properties in the late 19th century. For many years it has been used as an alternative to aspirin for the treatment of various ailments, but large-scale medical use stopped when the toxic side effects of acetanilide consumption occurred. This was enough to decide to use 35% hydrogen peroxide instead.
First, 35% peroxide is caustic and must be treated with the same caution as a strong acid. Hydrogen peroxide at 35% strength should be readily available in any quality hydroponic supply store. Stronger concentrations do not use added stabilizers.
The recommended dosage is to add 2-3 ml to each gallon of water, however I use 5 ml per gallon and have never had any problems. At each change of nutrients, treat your fresh water with hydrogen peroxide. The general idea is to let the hydroponic system circulate the hydrogen peroxide solution for about half an hour to allow the peroxide to act against pathogens and stabilize the solution before adding nutrients.
The beneficial effects of using hydrogen peroxide last about 4 days. There are some gardeners who add some peroxide to their nutrient tanks every 5 days between nutrient changes. If you do, follow the guidelines and always make sure your solution is thoroughly mixed before exposing your plants to the roots. Another option is to fill the nutrient tank with peroxide-treated water whenever it is low.
by Jason Willkomm