Four new metal-aluminum layered double hydroxides (LDHs), Mg-Al(OH) 2 PO 4 (1), Mg-Al(OH) 2 PO 4 PF 6 (2), Ca-Al(OH) 2 SO 4 (3), and Ca-Al(OH) 2 PO 4 PF 6 (4), were prepared by the coprecipitation method followed by mild hydrothermal processing at 60°C. Mg 2+ and Ca 2+ in solution with Al 3+ were titrated with NaOH over 3-5 h to yield Mg-Al and Ca-Al layered double hydroxides, respectively, incorporating PO 4 3− , PO 4 3− PF 6 − , and SO 4 2− anions in the interlamellar spaces. e isolated compounds were characterized with the help of XRD, IR, and SEM/EDAX, and their ability to remove scale-forming ions from the aqueous system was studied with the help of atomic absorption spectroscopy (AAS). e SEM micrographs of Mg-O-Al-OH and Ca-O-Al-OH layers intercalated with PO 4 3− and/or [PO 4 PF 6 ] 4− anions are similar consisting of uniform nanospheres with an average size of 100 nm, while the M-O-Al-OH layer of compound 3, intercalated with SO 4 2− anions, consists of hexagonal nanoplate crystals. In the infrared spectra, the characteristic absorption band for water molecules was observed in all the compounds. e XRD pattern showed that d 012 and d 104 peaks of M-Al-PO 4 LDHs corresponding to interplanar spacing of 3.4804 and 2.5504Å, respectively, shifted to higher 2θ values for the M-Al-PO 4 PF 6 system, which indicates a decrease in the interlamellar spacing as PF 6 − was incorporated along with PO 4 3− anion. e XRD pattern for Ca-Al-SO 4 LDHs was quite different, showing the presence of lowangle peaks at 2θ � 11.68 and 14.72°. e results of the column adsorption studies showed that there was a significant removal of Ca 2+ by all the compounds under investigation with an efficiency of 84-99%. However, compounds 1 and 2 remove Fe 2+ effectively with the efficiency of 98.73 and 99.77%, respectively; compounds 3 and 4 were shown to have little or no effect.