It is calcium carbonate coming out of solution.
Why it happens here
Dubai's mains supply is mostly desalinated and low in calcium, which sounds like it should prevent scale. Two things change that.
When water evaporates, minerals stay behind. Calcium concentrates over time.
Calcium carbonate is less soluble in hot water. Heater surfaces and salt cell plates are the hottest points in the system, so scale forms there first.
The Langelier Saturation Index
The index combines pH, temperature, calcium hardness, alkalinity and total dissolved solids into one number.
Between the two, balanced.
A pool can have every reading nominally in range and still be scaling if the combination is wrong.
Practical control
Use a sequestrant if hardness cannot be brought down.
Removing existing scale
Light scale comes off with an acid wash on the tile band. Heavy scale usually needs bead blasting, which is done with the pool drained.
What matters in Dubai
Dubai heat, dust and strong sunlight change pool water quickly. Swimming pool maintenance needs regular testing and a clean circulation system. Chemical treatment works properly only when the pump and filter are doing their part.
What to check before work starts
The existing pool or room should be inspected as a complete system. Visible damage may sit beside a separate problem in the pipework, controls, waterproofing or ventilation. A written scope should identify the affected parts and state which surrounding surfaces need protection or opening.
The maintenance approach should match the pool finish and the installed equipment. Salt systems, automatic dosing and standard chlorination have different service needs, while shaded pools behave differently from exposed pools.
Related pool services
The subject may connect with swimming pool construction and swimming pool maintenance. Swimming pool repair can be relevant as well. Swimming pool tiling applies where the shell or finish is opened. Sauna installation and steam room work are separate wet-area services.
- Swimming pool construction and renovation
- Swimming pool maintenance and water care
- Swimming pool repair and equipment work
- Swimming pool tiling and waterproofing
- Sauna and steam room installation or repair