There comes a day when your enjoying a nice day in your pool, when you notice the calcium line around the rile of your pool got noticeably bigger than when you last saw it.
What causes that line to appear?
It's actually caused by many different things that can change depending on your circumstances.
But they are all made of two different types of scaling.
What is the scaling mad out of and how can you get rid of it?
Type 1: Calcium Carbonate, which happens to be the easiest to remove... The easiest way to find out if you have this type of scaling is to drop a bit of Muriatic acid on it, (Every pool tech should have this on their truck) if it foams up or fizzes right away, then you have Calcium Carbonate, otherwise it won't do anything.
Type 2: Calcium Silicate, This type of scaling is much harder to get rid of. Simply apply the above test and if nothing happens, then this type of calcium is the culprit.
How do you get rid of it?
The nitty gritty way to get this stuff off is to break out the Pumice stone and scrub it off the old fashioned way.
Just be sure the stone stays wet, and that you don't use it on anything other than concrete or ceramic tile. Also be prepared to spend some time on it depending on the size of the area that needs the treatment.
Another way is to use some solution (many different kinds are available on the market) that your pool tech would suggest or by doing some research on the internet for different products with good reviews.
If the build up of this type of calcium is on the plaster or pebble tech of your pool, then a simple acid wash should do the trick to getting it all cleaned up.
Is another story, you can apply the above method, but be prepared to quite your day job if you want to get it looking new again.
The best (& easiest) way to get rid of this type of calcium, is to hire a pro that can get his media blast machine out there to blast it right off.
Just ask your pool tech if they or someone they know has the equipment to get the job done right.