The film on your shower door probably is not limescale

If you have searched for how to clean a shower door, you have been told to use vinegar, or a limescale remover, or something acidic. You may have done it and found it barely worked, and concluded you needed a stronger version of the same thing.

In Vancouver, you probably needed a different thing entirely.

Vancouver water is close to as soft as tap water gets

Metro Vancouver's published water quality reporting puts the hardness of the regional supply at roughly 3 to 4 milligrams per litre as calcium carbonate. Water is generally classed as soft below 60. The supply comes from three mountain reservoirs, off granite rather than limestone, so it arrives carrying almost nothing dissolved in it.

Limescale is dissolved minerals left behind when water evaporates. With that little in the water, there is very little to leave behind.

One caveat worth stating plainly: this is the regional surface supply. Parts of the Lower Mainland that draw partly on groundwater — areas of Surrey, Langley, Delta and Abbotsford — can be measurably harder, and the advice below is less true there.

So what is the white film?

Mostly soap and body oil, plus whatever else goes down the walls. Shower gel, conditioner, shampoo, bath products, skin oils. It dries onto the glass as a thin greasy layer, picks up dust, and goes cloudy.

It is worth being precise here, because the terminology causes the confusion. Classic soap scum — the chalky, gritty deposit — is a hard water phenomenon: soap reacts with the calcium and magnesium in the water to form an insoluble residue. That reaction needs minerals, and Vancouver water does not supply many. So the deposit on a Vancouver shower door tends to be softer, greasier and more of a film than a crust.

There is a second thing soft water does, which most people have noticed without connecting it. Soap lathers far more readily in soft water, so you use more of it than you need to, and it rinses off less completely. More product on the walls, less of it washed away.

Why the acid did not work

Acidic cleaners — vinegar, citric acid, commercial limescale removers — dissolve mineral deposits. They are the correct tool in Calgary or London. They are not designed to lift an oily film and they do not do it well.

What lifts grease is a surfactant, and usually an alkaline one: washing-up liquid, a general purpose degreaser, a bathroom cleaner sold for soap scum rather than for limescale. If you have been scrubbing a shower door with vinegar and getting nowhere, that is the swap to make.

Two things worth saying alongside that. Never mix an acidic cleaner with bleach; the combination releases chlorine gas, and bathrooms are small rooms. And check the label before using anything acidic on natural stone, which it can etch permanently.

The part that actually fixes it

Removing the film is a one-off job. Stopping it coming back is a habit, and it is a short one.

• Squeegee the glass after showering. It takes about fifteen seconds and it is the single most effective thing on this list, because a dry surface cannot dry a residue onto itself.
• Run the extract fan during the shower and for a while afterwards. Damp is what turns a film into something with mildew growing in it.
• Use less product. Soft water needs noticeably less soap and shampoo than the amount most people have got used to, and the excess ends up on the walls.
• Consider switching from bar soap to a liquid body wash. Bar soaps are more likely to leave residue; most liquid washes are synthetic detergents that leave less behind.

If it is not coming off at all

Two possibilities. Either it has been there long enough to need a proper mechanical clean rather than a wipe, or it is not residue.

Glass that has gone permanently cloudy and does not respond to anything is usually etched rather than dirty — years of hard scrubbing, abrasive products, or in older screens the glass surface itself degrading. Etching is damage, not soil, and no cleaner will fix it. Knowing which of the two you have is worth finding out before buying a fourth product.

The short version

In this city, reach for a degreaser rather than a descaler, squeegee the glass, and use less soap than you think you need. Most of the internet is giving you advice for someone else's water.