Our pool this morning.......This pool is located in the garden of our home in Cancun, Mexico. The water here is very hard. The pool water has been in the pool since it was finished almost 3 summers ago. In the past we used Muriatic acid and a brush to scrub the "bathtub" ring off of the pool perimeter several times a year successfully. This season we developed this thick scale that isn't phased by the Muriatic acid scrub. The only way I can remove it is with a paint scrapper and razor blade. The pool sides and bottom are covered with ceramic tiles. We've never had deposits build up on the stainless railing going into the pool in previous seasons. It took me about 3 hours to scape it clean. We use Triclor tablets, Hit OK, and chemicals to raise or lower the PH as needed and monitor the chemistry with a basic kit every week even when it's winter here. We also use a product called Cristalin Platinum which gives the water a blue hue and makes it really sparkle.
Scale deposits around entire pool at waterline as well as on underwater lights and stainless steel railing....
Closeup of scaly deposits
My readings using the Trouble Free Test Kit TF-100 this morning......
We cannot seem to find a way to chemically remove the scale deposits. So far the only thing that works is mechanical removal methods. To do that we will have to drain the pool and scape it down and refill. If anyone could suggest anything I could add to the pool chemistry that would resolve these deposits I would really appreciate it.
Sending you all warm Caribbean breezes and an advance thanks.