A calcium line will eventually form even though your tile or pebble is being brushed.  The sun and air bake and dry the calcium in your pool water to your tile or pebble more and more over time.  Once it gets too displeasing to look at, it will require a process called 'glass beading' to remove the calcium and renew the surface.  R & R does not perform this service, but we do have a few companies that we refer and would be happy to assist in lining up this service. 

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