Summer is over and you’re ready to shut down your backyard pool after a fun season. But like a lot of pool owners, you notice a chalky white ring has developed at the waterline. It has to go, but that may be a maintenance item you weren’t expecting.
What is it? And what can you do about it? For most owners, what you’re looking at is a ring of calcium. Over a couple of months time, the chemical balance of the water separates the calcium from the pool walls and it migrates to the “shores” of your pool, just like sand at the beach. Only it’s a lot harder to move, and it’s mercilessly stuck to your delicate glass pool tiles.
Homeowners are used to scrubbing things to keep them clean, so that might be your first inclination. People may mention acids, scrubbing solutions, and abrasive pads. You will inevitably get advice from people about using pumice stones and other sanding weapons to help you scrape the encrusted calcium off of very attractive and vulnerable glass tiles. Pay no attention to these people.
Working with muriatic acid is much more difficult and messy than it is worth, and any solution, pad, or sanding block that is abrasive enough to remove calcium build-up with relative ease will just as easily etch and scratch your tiled walls. There are three reasons not to use abrasives:
The best thing to do for your pool’s calcium ring is to call a professional bead blaster. Some may recommend low pressure glass beading, and others may recommend soda blasting, but in either case, you should be able to find someone with the right equipment and a sterling reputation.
The right pool cleaning service will know how to adjust the pressure and flow of the beads so that the calcium comes off, and the tiles remain undamaged. There is no need to drain all of the water, either. The tech needs just enough room to access the ring. All of the residual material falls to the bottom of your pool for routine vacuuming.
No matter how meticulous you are with balancing your pool’s chemicals, it’s almost certain you will find calcium clinging to the tile at some point. But the cost of hiring a pro to remove it is worth avoiding the risk of damaging your investment or making the problem worse in the long run.