💧 Calculator

Descale time calculator

How long to soak, how much to dilute, and what to rinse afterwards. Scale severity, acid and finish all change the answer.

3 acids4 finishesNo data sent

Your head

Warm water speeds up the reaction. Above 45 °C can soften plastic and rubber.

Soak plan

4hours
Dilution Neat Mix before submerging
Check at 2 h Look before the full soak

SafetyNever mix descalers, and never combine an acid with bleach.

Rinse & aftercare

  • Rinse the head thoroughly under running water.
  • Run the shower for a full minute before judging the result.
  • Clear remaining holes with a wooden toothpick.
Why the time changes with the finish

Chrome tolerates acid well; brushed, coloured and rubber parts are more sensitive and get shorter soaks at lower concentration. The calculator applies that as a multiplier rather than a different recipe.

What each descaler does

Vinegar is dilute acetic acid: slow, cheap, safe on chrome, and smelly. Citric acid is faster and odourless, and is the better choice for a small bathroom. Proprietary descalers are stronger acids — fast, but less forgiving on finishes and on skin.

All three work the same way: they convert calcium carbonate into a soluble salt. None of them removes silica, iron staining or biofilm, which is why a soak sometimes does nothing.

When not to soak

  • The head has electronic components or an LED — check the manual.
  • The finish is gold or PVD-coated: use citric acid at half strength.
  • The head is cracked: acid will not help and the crack will spread.
  • You have already soaked twice with no change: the restriction is probably upstream.
Acids are irritants. Ventilate the room, wear gloves, keep containers away from children, and never mix a descaler with bleach or another cleaner. Manufacturer care instructions take precedence.