A Green, Slippery Pool Deck
A pool deck that has gone green is not just untidy. Algae on wet concrete or pavers is one of the most slippery surfaces on a residential property, and it is right where people walk barefoot.
Why the deck greens before anything else
A pool deck is wet several times a day from splash-out, wet feet and evaporation off the water. Add the shade thrown by a screen enclosure and surrounding planting, and it never fully dries.
That is exactly what algae needs. It establishes in the surface pores of concrete and in the joints between pavers, then spreads outward from the coping toward the edges of the deck.
Travertine, coquina and textured concrete hold it hardest, because the texture that makes them slip-resistant when clean also gives the organism somewhere to sit.
The slip risk is the real problem
Wet algae has roughly the friction of wet soap. On a deck surface specifically chosen for grip, that is a meaningful hazard — and pool decks are where people move quickly, barefoot, often children.
The danger is worst in the transition zone right around the coping, where the surface stays wettest and the growth is heaviest.
If your deck feels slick underfoot when wet, that is not the texture wearing out. That is a biological film you can remove.
What not to do
Do not pour chlorine on it and leave it. Pool chlorine is not formulated for hardscape, will not kill the organism at the root, and can bleach coloured concrete unevenly.
Do not use a turbo nozzle to spot-clean the worst patches. It etches the surface, leaving permanent rings that hold dirt worse than the algae did.
Do not scrub travertine or coquina with a wire brush. Both are soft stone. You will scratch the finish and open more pore structure for the next colony.
How we clean it
The deck is treated with a cleaning solution that kills algae at the root, given dwell time, then cleaned with a surface cleaner that applies even pressure across the whole slab rather than the arc marks a hand-held wand leaves.
Runoff is directed away from the pool and the deck is rinsed thoroughly, along with coping, steps and the bottom track of any screen enclosure.
Grip comes back immediately, and because the organism is dead rather than displaced the deck stays clear far longer than a straight pressure wash would give you.
Questions we get about this
Is a green pool deck actually dangerous?
Will cleaning affect my pool chemistry?
Can you clean travertine and coquina safely?
How often should a pool deck be done?
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