I'm surrounded by veterans that insist on first-hand experience with vinyl damaged by untreated soft water.
So I'm going to put my employee discount to good use and design an experiment. Unless you all tell me that it's not feasible. I'm not looking to publish a paper or anything - just for my own peace of mind.
Yes, I know that that there's no reason whatsoever besides aforementioned industry guidelines to think that water with a low level of calcium saturation would damage vinyl.
1) Fill two translucent milk jugs with tap water.
2) Adjust to something reasonable for pool-typical water balance:
PH: 7.4-7.6 (comes out of the tap this way)
3) Leave one jug at fill-water CH (about 30.) Adjust second jug to 250ppm.
4) Drop a small piece of vinyl liner in each jug and leave them outside for a week. Keep aforelisted numbers in range.
1) Will putting the caps back on the jugs and shaking them around every day adequately represent circulation?
2) Will test strips be accurate enough for the purpose of this test? I foresee problems with removing enough water from the
jugs for several DPD tests each day.
3) Is a week long enough?
4) Will this tell me anything useful at all?
Thanks, mysterious internet geniuses.