You should give it done dry pulls, hit it w /o pressing the fire button, this will help keep your carto well saturated, when it gets in your mouth, and when you stop seeing bubbles come up that means your on the flooded side as opposed to the dry hit side, I always give some e dry pulls, and or extra pulling after releasing the button to help keep carto saturated, this comes into play more with thicker juice all tho it is not as big of a deal as people will lead you to believe.
I always pull my carto tanks up, opposite from pic above, haven't had any problems with Orings, just keep them juicy.
Keep your 510 connector clean.
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