White buildup on brick

[VELO]

I have a brick wall on one side of my pool.. the spa cascades over this wall. Over the years a white buildup has collected on the brick. Anyone know what this is and how to get rid of it?

VELO

 

[cfherrman]

Do you use solid forms of clorine?

 

[pooldv]

It is likely either calcium scale or efflorescence. Need a pic to tell which. Water test results would help also.