Filtration . . . and time.

You could see if it will settle:
1. Raise the chlorine level HIGH.
2. Turn your pump off for 24+ hours.
3. After it settles (if it settles), adjust your returns upward so they don't disturb the floor.
4. Carefully vacuum the calcium dust to "WASTE".

(Not an option, if you don't have a multiport with a 'waste' position.)