Green algae in swimming pool — Madrid, Madrid
Green, slimy water and algae growth on pool walls or floor indicate that the sanitizer level has dropped too low, the filtration system isn't running enough hours, or the pH is out of range. Left untreated, algae can clog the filter, stain the plaster, and make the pool unsafe to swim in. A pool technician can test the water chemistry, perform a shock treatment, brush and vacuum the surfaces, clean or backwash the filter, and adjust the chemical balance to prevent recurrence.
Who to call
For this problem in Madrid, call a: Zwembadtechnicus
Vind een Zwembadtechnicus in MadridSymptoms to look for
- Pool water turns green, cloudy, or has a slimy film on the surface
- Green or black patches growing on pool walls, steps, or floor
- Filter pressure gauge reading higher than normal (clogged filter)
- Strong chlorine smell yet low free-chlorine test result (chloramines, not free chlorine)
Spoeddienst in Madrid
Emergency services in Madrid respond within 30–75 minutes in the central districts. Callout rates run €55–€140 plus €45–€75/hour including IVA — among Spain's highest after Barcelona. Winter cold snaps drive burst-pipe and heating-failure surges that can stretch waits; verify the contractor is a registered instalador autorizado with the Comunidad de Madrid before granting entry.