Benefits Of Acid Washing
- Removes build-up of calcium and other scale from the pool surfaces
- Enables the pool-owner to keep the pool sanitised and looking great!
- Restores the glass-smooth surface to the tiles
Cleaning the tiled surfaces
Non Technical Version
If your pool water has been too alkali, chalk builts up on the tiles like fur in a kettle.
We basically get into the drained pool and de-scale it, leaving it clean and shiny.
This is a dangerous and specialised job and should not be attempted without training and special protective clothes etc.
If the pH in your pool has been allowed to get too high you will almost certainly experience a build-up of lime-scale. This is largely calcium from the minerals dissolved in the pool water and the build-up changes the way the tiles feel - instead of a glass-smooth finish the tiles feel rough and abrasive.
When calcification is severe it is almost impossible to keep the pool clean, sanitised and looking good.
The reason for this is that the surface of the lime scale is pitted with millions of tiny holes. These holes are so small that they can be regarded as 'dead spots' in the pool water circulation and therefore do not receive fresh supplies of chlorine.
Algae spores can take up residence in the holes and proliferate, giving a green tinge to the lime scale. The next time the pool is super-chlorinated the algae will be killed and turn brown but, locked away in the pores as they are, they will remain as an unsightly brown stain.
The solution to the problem is to drain the pool and remove the lime scale with acid. This is not a job that should be attempted by the average pool-owner as it involves the use of corrosive chemicals which can be hazardous to health.
Before and after photographs from a badly calcified pool in Maro, Nerja, Spain.
Sand Filter damage
One other, perhaps unsuspected, effect of high pH is the deposit of calcium on each grain of sand within the sand-filter.
This results in the grains of sand accreting together to form a solid lump of rock, as in the photo above. The filter is ineffective and the sand must be replaced. Often it is very difficult to remove the accreted sand without damaging the filter body or collector array. We manage to save almost all of them (taking great care not to damage the delicate plumbing within), re-fill them with Zeolite and give them another 5-7 years of life.