Water filtration and treatment

Only if a test says so. On municipal water, read your utility’s annual water quality report first. It is free and it tells you what is in the supply. Then test your own tap for lead if the plumbing predates 1986. Many municipal households need nothing more than a carbon filter for taste. On a private well, nobody is treating or testing anything upstream, so a laboratory panel is essential and treatment often genuinely is too.

That demonstration proves very little. Precipitation tests react to ordinary dissolved minerals that are harmless, and electrolysis demonstrations will discolour any water including bottled. Neither identifies a contaminant or a concentration. Ask for a certified laboratory report instead, if the seller cannot provide one, the diagnosis does not exist.

A softener removes hardness minerals, calcium and magnesium, by ion exchange, and does nothing else. A filter removes or reduces specific substances depending on its media: carbon for chlorine, taste and some organics; oxidising media for iron and manganese; sediment cartridges for grit. They solve different problems, and a softener sold as a general-purpose water improver is being misrepresented.

No. Hardness is not a health concern. It is an equipment and convenience issue. It scales water heaters and tankless heat exchangers, furs up shower heads and aerators, spots glassware, stiffens laundry and makes soap less effective. Those are real costs worth addressing, but they are not health risks.

They do something, but not what softeners do. Template-assisted crystallisation devices alter how scale forms so it is less likely to adhere to pipe and heater surfaces. That can genuinely reduce scale deposition. But they do not remove hardness minerals, so the water will still spot glassware and still resist soap. If your goal is scale protection they may suit; if your goal is soft water they will disappoint.

Hydrogen sulphide, usually from sulphur bacteria or naturally occurring conditions in the aquifer. The treatments are aeration or an oxidising filter, depending on concentration. Before installing anything, check whether the smell is only on the hot side, if so, the reaction is happening in the water heater with its anode rod, and swapping the rod is a much cheaper fix.

A properly certified one will, but the type matters. Look for NSF/ANSI 53 certification for lead specifically, or NSF/ANSI 58 for reverse osmosis. Point-of-use is the right approach, since lead only matters in what you drink and cook with. Bear in mind that lead comes from your own plumbing rather than the source, lead-tin solder on pre-1986 copper, brass fixtures, or an old lead service line, so replacing the source is the permanent fix.

It inactivates bacteria, viruses and protozoa by exposing them to ultraviolet light. Nothing else. It does not remove iron, hardness, sediment, taste or chemicals, and it needs clear water to work at all, so it goes last in a treatment train after filtration. The lamp must be replaced annually because its output degrades long before it stops glowing.

A laboratory panel is $150 to $450. An under-sink reverse osmosis unit is $400 to $1,200 installed. A metered softener is $1,200 to $3,000. A full well treatment train with several stages runs $4,000 to $10,000. If you are on municipal water and being quoted $5,000 or more for a whole-house system, ask which laboratory result justifies each stage, often the honest answer is a $400 under-sink unit.

More than people expect, and it is not optional. Sediment cartridges every three to six months, carbon every six to twelve, softener salt monthly with an annual brine tank clean, UV lamps annually, RO prefilters every six to twelve months and membranes every two to five years. A spent carbon cartridge becomes a bacterial habitat, so neglected equipment is genuinely worse than none. Retest the water annually to confirm it is all still working.