The water tastes of metal and the bath has turned orange: the three borehole complaints, named

Borehole water arrives with a small vocabulary of complaints, and each one is a specific chemistry with a specific answer - the reason most households buy the wrong filter is that they describe the complaint as "the water is not right" and the shop sells them a general something. Three names and their stains, and the page that reads like a doctor's chart because the symptoms do the diagnosis.

Iron - the metal taste and the orange stain

The taste of a penny, the tea-ring that will not lift from the kettle, and the orange streak running down a white basin: dissolved iron, common as the geology it came from. It is mostly an aesthetic and laundry problem, not a health one - the honest first sentence - with the one caveat that iron bacteria ride the same water and build the slime that fouls a well. The treatment that actually works is the one the filter sellers skip the detail on: oxidise first, then catch - an aeration stage (even the old trick of letting the roof tank's inflow fall through air does a third of the job), or the Greensand/oxide-media filter that turns the dissolved iron into rust you can see in the tank before the tap, and backwashes to clean itself. A plain sediment sock softens the story but does not take iron out of solution - that is the product-class mismatch this paragraph exists to prevent.

Sulphur - the smell of a struck match in the water, not the drain

The rotten-egg complaint is usually the drain's bacteria (the water article's trap-clean paragraph handles that test - smell the running water, then the drain with the water off). When the water itself smells of it, hydrogen sulphide is coming from the well, and the same oxidising filters catch it; the household's extra note: a chlorine shock of the well by a professional ends the bacterial version, and the smell returning in a month is the well needing its silt and the screen dealt with, not a bigger chlorine dose.

Hardness - the scale the kettle article already knows

The chalk in the element and the soap that will not lather are the same calcium story; the bathroom's own answer is the kettle page's (vinegar, descale, do not wait for the flow to thin) and the whole-house answer is the ion-exchange softener, with its honest trade: salt, backwash water, and softened water is not for the drinking tap in any number of health contexts - the desk's standing line is soft the bathroom, drink the kitchen tap from a pitcher or the boiled line, and the two-tap plan is the version the households that do this properly live by.

When the answer is the lab, not the tin

Three signs skip every filter conversation: a salty or brackish taste (salinity - no domestic filter takes it out, the borehole itself needs re-thinking or the neighbour's soakaway has met your aquifer and that is a siting problem with a health tail), a chemical or fuel note at any strength (the surface has reached the water table and the source needs finding by the proper people - this is the desk's emergency line on a boring-sounding page), and anything new in a well that has always been quiet - the change in the water is data, and the plate counts and the nitrate figure are the whole annual-test story the borehole article already asks for. The summary for the shop, in the sentence that ends most wrong purchases: name the complaint, show the stain, then buy the machine whose media answers that name.