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My dealer made it sound like I should change it at every water change.
I think my dealer is either misinformed or just trying to sell me more N2 carts. Back in November, I was in his store and I told him I was changing my water after 6 weeks and he told me that I would need to change out the N2 cart. It didn't seem right but I followed his instructions. I wonder if taking it out of the water has anything to do with his thinking. Doesn't sound right to me, that is why I am asking.Maybe I should keep is submerged in the old spa water until the new water is is in the spa and I will just transfer it over without letting it dry out?Jonathan
I change water and N2 cartridge every 6 months.