"is there a safe period of time that passes before corrosion of plaster likely?"
Preparing pool for winter in Houston TX; this will be the start of BBB, too. CYA was at 160 last week, so emptied 1/2 the pool and brought it down to 80 this last weekend and intend to do another 1/2 to bring down to 40 next week.
Before 1/2 empty:
FC: 20
CC: 0
PH: 7.8
TA: 110
CA: 250
CYA: 160
After 1/2 empty, then refill:
FC: 23 (shocked)
CC: 0
PH: 7.8
TA: 240
CA: 150
CYA: 80
After 1 gallon muriatic acid (two part introduction) (yesterday):
FC: 21
CC: 0
PH: 7.0
TA: 120
CA: 150
CYA: 80
Temps:
Out: 50 low, 75-80 high
In: 70-72
Calcite Saturation Index:
-.7 to -.8
Preparing pool for winter in Houston TX; this will be the start of BBB, too. CYA was at 160 last week, so emptied 1/2 the pool and brought it down to 80 this last weekend and intend to do another 1/2 to bring down to 40 next week.
Before 1/2 empty:
FC: 20
CC: 0
PH: 7.8
TA: 110
CA: 250
CYA: 160
After 1/2 empty, then refill:
FC: 23 (shocked)
CC: 0
PH: 7.8
TA: 240
CA: 150
CYA: 80
After 1 gallon muriatic acid (two part introduction) (yesterday):
FC: 21
CC: 0
PH: 7.0
TA: 120
CA: 150
CYA: 80
Temps:
Out: 50 low, 75-80 high
In: 70-72
Calcite Saturation Index:
-.7 to -.8