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There are a few factors re: cover longevity:--Location--Is it in full sun all day? Is is subject to "tree trash"?--Quality--Covers differ greatly in construction quality. I would guess that most manufacturers have theirs made by another company. Retailers might chime in if they know of specifics re: their brand(s).--Maintenance--Is the cover cleaned regularly? Is 303 Protectant used regularly to condition the vinyl?--Handling--Is a cover lifter used as opposed to dragging the cover off the spa?There may be more considerations but these are "first out" for me.My cover would have lasted more than 4 years had a tornadic wind not deposited it in my neighbors yard. I've ordered a custom cover here from the good Doc and am anxiously awaiting its arrival. I'm sure it will be MUCH better than my original cover even though it would have survived nicely even with direct sun all day for 4 years this July.HTH... 8-)
When I shock the tub I always have the cover open.
There is nothing wrong with the vinyl on the cover. I assume thats why all the questions.? Correct me if I'm wrong. My cover is saturated with water (it is very heavy (wife can no longer lift it) even with a cover lifter). When I shock the tub I always have the cover open. What can be done to prolong the life of the cover?
If your vinyl is still like new, buy a foam insert only. Will save you some money. 8-)
Open, or OFF? If just open, the side facing the spa will degrade and become heavy.