Best Answer: Well Cooli_Gal3, you are pushing the time limit for leaving it on as it is. Also try to find another light to use as a nightlight as the lava lamp uses too much energy.When the time comes that they completely eliminate the use of incandescent bulbs your lava lamp will no longer work. read more
From my own lava lamp experience, I have used it as a night light while I sleep, or have forgotton to turn it off and left it on all night long. When it's on for a long period of time, like over 8 hours, the glass becomes very warm, the lava breaks into smaller pieces, and the lava has weird bubbles that form in it. read more