There is some hardware on the ladder that must be stainless because it has not changed. I know galvanized steel would be showing rust by now seeing its the original hardware the ladder came with.

I have an 18', 52" pool. I have never checked levels through the winter and have only had one time where it was cloudy when removing the cover. I had looked in it a couple of weeks before and it was clear. I remove my pump/motor and store it in my shop during the winter.

I usually add algecide and two bags of shock before covering it. We have very hard water here, its always high on hardness with strips. I know those have limited accuracy so I just use them to see a ballpark figure.