I'm not sure if this has or hasn't been discussed before, but I thought it might be helpful. I have read some posts on this forum and others from users complaining of a "vapor lock" issue, which is stated as the Aspire Cleito tank is designed in such a way that when the user vapes the liquid, the cotton then wicks more liquid which causes the fluid level in the tank to decrease without a way for air to get in to replace the spent liquid, and as such, this vacuum pressure will not allow more liquid to wick, causing the cotton to burn. I have to admit, I haven't had any issues with this, but it's because I read the instructions from the get go and took them to heart. The manual for the Cleito explicitly informs users not to overtighten the top cap after filling the tank with liquid. It doesn't say why, but I never really thought much of it, and I never had the "vapor lock" issue. Months later I had given my wife my original Cleito tank and upgraded to the Cleito 120 (even now with the RTA which is awesome!) and she got my Cleito as a hand-me-down. Well, wouldn't you know it, she was going through her atomizers at the rate of 1 per day and for the longest time I couldn't understand why. Then when she asked me to change the atomizer for her one time I immediately realized she was overtightening the top cap. After replacing it myself, and instructing her not to tighten it like that, the atomizer lasted 3 weeks. So, I experimented myself. Tightening the cap slight causes no bubbles to appear after taking a hit off the tank then removing the top after, whereas if I overtighten the tank, take a hit, and then remove the cap, bubbles appear at the cotton, clearly showing that I had created a vacuum before.
So, there you have it. If you're burning through atomizers daily, finding muted flavor often, lack of vapor production, getting dry hits too soon and/or too frequently, check to make sure you didn't overtighten the top filling cap on the Cleito or the metallic separator on the Cleito 120. The gasket works really well, you barely need to tighten the tank to prevent liquid from leaking out the top; it never will. But if you overtighten even a little bit, it will prevent the gasket from allowing air to vent through and replace the consumed liquid, causing the dreaded "vapor lock" and preventing the cotton from wicking, which will always lead to dry burn and ruined cotton and atomizers.