There are many plants which have the ability to accumulate large amounts of heavy metals and one of them is the aquatic fern, Azolla filiculoides. Toxic metals constitute a serious health risk because they accumulate in soils, water and organisms. One of the methods for removing these pollutants from water and soil is the use of plants. The aim of this study was to test the ability of A. filiculoides to adsorb Ni from polluted waters. The maximum uptake of nickel ions by the collected A. filiculoides biomass under
the optimal conditions was approximately 45.32 mg/g dry Azolla. Desorption experiments indicated that EDTA was an efficient desorbent for recovery from nickel ions.