I let the water balance slide during the winter and white deposits formed throughout the pool and spa. They're quite hard and I suspect they're calcium deposits. Calcium dropped down to about 120-140 ppm during the winter and it is currently at 180 ppm.

For our pebble finish pool, these are today's readings:

Chlorine: 1 (salt was low, added it and the chlorinator is running now)
Calcium: 180
TA: 100
pH: 7.4
CYA: 40
Salt: 3000

What is the most efficient way to remove these deposits? Like I said, I assume they're calcium but am not positive. A Scotch pad and a plastic scraper have removed most of the deposits in the spa but I simply cannot use the same process in the much larger pool.

Deposits on a bench:


Deposits on wall: