Depending on the quality of the irrigation water most irrigation systems will need to be cleaned using some form of chemical treatment to keep drip emitters dripping. There are several drip irrigation cleaning chemicals available. The types of obstruction that can be effectively cleaned, the method of application and the risks associated with use differ greatly between chemicals. The table below gives an overview of which groups of chemicals can be used for various types of irrigation system clogging issues and the hazards involved in their use.
Acid Treatment - Hydrochloric Acid, Sulphuric Acid, Nitric Acid and Phosphoric Acid are commonly used to dissolve precipitates of lime (calcium carbonate) and calcium residue from fertilizer applied under high pH conditions from in the irrigation system. It may also be used to clean the drip emitters’ water passages from other mineral deposits like ferric oxides. Acid treatments are not effective against algae and other organic matter problems. Acids must be handled with extreme care and will burn skin or plant material on contact.
Peroxide Treatment - Hydrogen peroxide is a strong oxidizing agent. It releases oxygen atoms that react quickly, oxidizing organic matter. Peroxide can help to decrease blockage from biological slimes and iron reducing bacteria, but is of limited effectiveness against mineral scale. Direct contact between hydrogen peroxide and fertilizers or other chemical products could create a thermal reaction which could cause the tank to explode. Peroxides must be handled with extreme care and will burn skin or plant material on contact.
Chlorine - Chlorine has been used to oxidize organic material and kill algae within irrigation systems. However it was found that after the oxidation and disinfection process, organic chlorides, which produce carcinogenic compounds, such as Trichloromethane, started to appear, and the process also contaminates the environment. Chlorine is extremely toxic to animal and plant life and must be used with extreme care.
Phyto-Cat - A fermentation of organic plant materials with a small amount of synthetic surfactant, Phyto-Cat oxidizes minerals and accelerates the decomposition of organic matter. Phyto-Cat is non-toxic and safe to handle.