All fertilizers, granular or liquid, are corrosive to some degree. Liquid fertilizers are corrosive on steel, brass, copper, zinc, some aluminium (and their alloys) and concrete. Summit recommend using equipment that comes into contact with liquid fertilizers be made from polythene, PVC, ceramic or stainless steel. Some grades of aluminium are suitable. At the end of each spraying period, all equipment that has come into contact with liquid fertilizer should be washed thoroughly with water to remove liquid fertilizer. Anti corrosion materials can be used to protect susceptible components. Use of trace elements in the spray will increase the corrosion risk.