The results of investigation of properties (solubility, antiscaling, anticorrosive, algicidal, bactericidal) of glassy copper-zinc-containing phosphate composition (Cu–Zn–FC), which is obtained by waste-free ecological technology for the purpose of corrective treatment of make-up water in centralized heating systems, are presented. The synergetic effect of the joint presence of long-chain phosphates, alternating copper and zinc cations in the composition is revealed, which strengthens, evenly distributes the protective film on the surface of the system elements and provides maximum efficiency in the fight against salt deposits, corrosion, biofouling.