What additional compounds are commonly combined with chelated copper products?

• A. TEA (triethanolamine) and EDA (ethylenediamine).
• B. Sodium nitrate and lime.
• C. Ammonia and chloride.
• D. Sodium sulfate and calcium.

Answer: (A)

Chelated copper products rely on chelating agents to keep copper ions dissolved and available in water. Organic ligands like triethanolamine (TEA) and ethylenediamine (EDA) bind to copper, forming stable complexes that resist precipitation as copper hydroxide or carbonate in hard water or at different pH levels. This stabilization is what makes the copper more effective as an algaecide, since it stays in solution rather than falling out of solution. The other options are inorganic additives or pH/ hardness adjusters that don’t provide the same stabilizing copper chelate function, so they’re not the typical companions to chelated copper products.