Which filtration method can remove dissolved metals?

• A. UV light
• B. Sediment filters
• C. Activated carbon filters
• D. Reverse Osmosis and KDF

Answer: (D)

Dissolved metals are ions suspended in water, so treatment must target ions rather than just particles or microbes. Reverse osmosis does this by forcing water through a semi-permeable membrane that blocks most dissolved ions and salts, so metals are largely left behind in the reject stream and the filtered water has much lower metal content. Pairing it with KDF media — a copper-zinc alloy that catalytically reduces or precipitates certain heavy metals and also lowers chlorine — enhances removal and protects the system, yielding even cleaner water. Other methods like UV light, sediment filtration, or activated carbon mainly address microbes, particulates, or organics and don’t reliably remove dissolved metals on their own, making the combination of reverse osmosis and KDF the most effective choice for dissolved metals.