Growth on tiles

[mizzamouse]

Hi,

I have some growth on the tiles under and around where the water feature is. It appears to be some type of calcium buildup. I’ve tried scrubbing with a little acid but didn’t seem to remove much. Any idea what this is and how I can get rid of it?

Thanks!

 

[mknauss]

Appears to be Effloressence.
Read Efflorescence - Further Reading