We have used a spa blanket since we first got our tub about 1 1/2 years ago. For the longest time, maybe even since the tub was new, we have been getting a light, golden brown line around the water line in our tub. It is not all the way around the tub, but is definitely there on a couple of sides of the tub. I’m not sure what made me think of it, but the other day I took the spa blanket off the tub and now the line around the tub is no longer appearing. I wonder if anyone else has had this experience?
And just so you know, the spa blanket we have is not one of those bubble wrap ones. We got it from Roberts Hot Tubs.