According to lava lamp manufacturer Haggerty Enterprises, lava lamps, originally called Astro Lamps, were invented in 1963 by engineer Edward Craven Walker. Two Chicago-based entrepreneurs began manufacture of the lava lamp in 1965, launching a cult-like phenomenon that persists decades later. Though the cause of lava-lamp cloudiness is to date unknown, this foggy goo affliction may leave lava-lamp aficionados feeling not so far out. According to lava light site Molten Meditation, admirers of the retro icon can restore their lamps to working order with some basic materials and a little TLC.
Begin with a lava lamp cooled to the point that the wax inside has solidified. Fit the wrench around the cover at the base of the glass enclosure and unscrew the cover to remove.
Pour the liquid off the inside off the lamp down a drain, taking care not to disturb the wax. Gently rinse the inside of the lamp, directing the stream of water against the top edge of glass rather than directly onto the solidified wax. Pour off water.
Repeat the rinsing until water runs clear, showing no signs of bubbles or oily residue. Fill a final time with clean tap water and place the lamp back in its base, leaving the lid off. Turn the lamp on and allow the lava lamp to heat until the wax has fully melted.
Drip three droplets of dish-washing liquid into the lamp.
Stir 50 g of Epsom salts into a half-filled glass of water until completely dissolved. Continue to add Epsom salts to the glass 1 tsp. at a time, stirring after each addition, until they no longer dissolve. Place the glass in a bowl of hot water and allow to stand for five minutes, or until all salt crystals have dissolved.
Dip the straw to the bottom of the saltwater glass and place your finger over the end. Keeping your finger in place, transfer the straw to the uncovered end of the lava lamp and press it to the inside rim of the lamp neck. Release your finger from the end of the straw, allowing the saltwater to drain into the lamp.
Wait five minutes, observing the lamp. Drip in one straw of saltwater at a time, observing between additions. Watch for the formation of large wax globs that float all the way to the top and then sink slowly to the bottom of the lamp. Once this occurs, your lava lamp is cured of cloudiness and restored to normal working order.