Drinking glasses
A cloudy glass is two different faults with the same appearance, and only one of them can be cleaned. Telling them apart takes about a minute.
Start here
What this is, what tends to go wrong with it, and what to do about it.
What tends to go wrong
A hard, chalky calcium carbonate deposit left by hard water. Dissolved by acids, essentially untouched by detergents.
Why it is difficult: Water hardness, Crystallisation, Adhesion and cohesion
What hard water leaves behind when it evaporates instead of being wiped away. A mineral film, not dirt, and the fix is at the drying stage.
Why it is difficult: Water hardness, Evaporative deposition
- Cleaning product residue· no established method
What the last clean left behind. It attracts soil, so the surface gets dirty faster — and the usual response is to use more of what caused it.
Why it is difficult: Residue and resoiling, Soil shielding, Why different surfaces get different dirt
In detail
Glasses that come out of a dishwasher cloudy have either a deposit on them or damage in them, and the treatments do not overlap. A deposit is limescale or a mineral film left by hard water, sitting on the surface — it dissolves in a mild acid and the glass comes back clear. Damage is etching: the alkaline detergent and heat have leached components out of the glass surface over many cycles, leaving a roughened layer that scatters light. Etching is irreversible, and no product reverses it, whatever the packaging says. Preventing etching is the only useful response to it, and the levers are the ones the dishwasher manufacturer names: less detergent in soft-water areas and the shortest cycle that gets the glasses clean, since excess alkalinity with nothing to buffer it is what attacks the glass.
Related
- Drinking glasses is commonly affected by Limescale
- Drinking glasses is commonly affected by Water marks
- Drinking glasses is commonly affected by Cleaning product residue
Sources for this page
Sources
Owner's Manual: Dishwashers GSD4500, GSD4800
GE Appliances · Manufacturer documentation
Relied on for: That the manufacturer identifies cloudiness on glassware as permanent etching caused by soft water and too much detergent, prevented by less detergent and the shortest cycle that gets glasses clean. (states this directly)
Glass Technical Paper FB01-00: Proper Procedures for Cleaning Architectural Glass Products
National Glass Association (NGA) with the International Window Cleaning Association (IWCA), 2023 · Trade or professional body
Relied on for: That glass can be permanently damaged if improperly cleaned and that surface damage is not reversible by cleaning. (inferred from the source; not stated directly)