Chloramine: the disinfectant that doesn't leave on its own.

Ask most people what is in tap water and they say chlorine. In Los Angeles, as in many large American cities, the main disinfectant is actually chloramine: chlorine bonded with ammonia. Utilities use it because it is more stable than chlorine and keeps water disinfected across hundreds of miles of pipe. It does that job well. The same stability is why it behaves differently in your home.

Chlorine vs chloramine

Plain chlorine is volatile. Let a glass of chlorinated water sit out for a day and most of the chlorine gasses off by itself. Chloramine does not. It stays in the water, in the glass, through the kettle, into the shower steam. Whatever amount arrives at your tap is the amount you drink, cook with, and bathe in.

To be clear about safety: chloramine levels in city water are regulated and the water meets federal and state standards. This is not a contamination story. It is a comfort, taste, and equipment story.

Where you notice it

• Taste and smell. The faint swimming pool note in tap water, coffee, and ice.
• Skin and hair. Disinfectants strip oils. Combined with LA's hard water, that is the dry, tight feeling after every shower.
• Rubber and gaskets. Chloramine is harder than chlorine on rubber plumbing parts, a known factor in the aging of fixtures and appliance seals.
• Fish tanks. The classic tell. Aquarium owners must neutralize chloramine specifically, because letting water sit, the old chlorine trick, does nothing.

Removing it takes the right carbon

Chloramine is removed by activated carbon, but slowly; the ammonia bond resists. Two grades matter:

Granular activated carbon (GAC), the coconut shell media in every whole home system we install, treats chlorine and chloramine as water flows through the tank. For most homes it is enough.

Catalytic carbon is carbon engineered with an altered surface that chemically breaks chloramine down rather than just trapping it. It is the industry's best answer for chloramine and for sulfur odors. On our systems it is a $100 upgrade, and we recommend it when a customer is sensitive to the taste, or when a water report shows chloramine on the higher side.

For drinking water, the reverse osmosis system adds two more carbon block stages plus the membrane itself, which is why RO water carries no disinfectant taste at all.