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You only have to leave the cover open if you're shocking the spa. This allows the chlorine to oxidize out and not into your cover. Just balancing pH or alk is totally fine to close it up.For clarity, is there a difference between this "clean cycle" and just turning the jets on and walking away? Don't most spas have a 15 or 20 min cycle on high speed? :-/Steve
The "Clean" button turns on a jet pump for 10 min. If you turn the jets on and walk away it will run for 2 hours.
Soak-king is correct.Term