Deposits on plaster and mottling of plaster

[nlt999]

Hi!
I drained my 18000 gallon concrete pool that I built myself 7 years ago, to do some maintenance on it. Before draining, I called the company that plastered it and asked about mottling of the blue plaster surface... they said that was not unusual. After draining I found that the originally medium-blue plaster had what looks like white-ish scale on much of it and some drippy-looking white deposits sticking to the sides and white bumps in places on the bottom. The drippy deposits can be removed reasonably easily with a razor blade. I've included photos.

Our water here is very hard and my TDS has been high for a while (about 3000 last checked). I probably should have emptied and refilled the pool sooner. Question now is: Should I acid-wash it? will these deposits cause future problems? Should I do anything else before refilling??

Appreciate any input! Nick