On a mountain above Honolulu at a height of around 1000 ft. up, on a 2,300 ft. mountain (approximately), where my neighbor (north east and above us being about 20 ft higher) and I both live we have an issue with iron staining from volcanic dust blown in by trade winds averaging 16 mph to 24 mph, this past week they have averaged 30 mph to 45 mph. These winds for the most part blow from a north easterly direction.
However my pool has always stained nearly twice as fast as my neighbors and I now think I might know the reason.
The roofer who worked on our house, replacing some cracked tiles, asked me if I had iron staining problems with my pool as it is surrounded on three sides with red clay tiles, our house on the south east close to the pool, our small pool gazebo on the north west close to the pool, and my neighbor’s very large roof on the north east side above us, very little of my neighbor’s roof falls over their pool. We both have red clay roof tiles. The roofer told me that red clay tiles contain a fair amount of iron that is what gives them the color of red. The roof as it gets older, both of ours are over 20 years old, with a life expectancy of 50 to 75 years, start to flake off dust which slowly weakens them. In his experience persons with pools where red tile roofs are situated north of the pool, or close to the pool on any side, all have this issue, on top of the wind born volcanic dust. Being more likely IF the pool is situated south or south west of the tile roofs, in Hawaii, as this is the main direction of our wind north east to south west.
So it seems that on very windy days the little red particles I catch in our pool cleaner's socks is not all dirt as I thought it was but probably bits of roof dust/particles. After a month or so the socks do go from white to orange in color, but by that time the socks normally need to be changed as they may have holes in them.
Well at least I now know, maybe, why it stains twice as fast despite all I do to prevent it. Unfortunately when the time comes to replace it I might have moved on to the land of eternal pools.
So if you are building a house with a pool in a windy area something to think about.