Cloudy water and "lazy" lava

[Javier]

Hi, I live in Monterrey, México, where summer is very, very hot (about 40°C). I don't know if that affects how lava lamps work, but I've recently bought a 2nd hand lava lamp at the flea market and it worked fine for about 4 days; then it´s water started to look cloudy and lava delayed a lot in floating after I turned the lamp on. Sometimes it gets stuck on the lamp bottom. The only thing I did was to "straighten" the bulb position, as it was inclined when I bought it, and I feared the lamp could break because of odd heating. I mean, I thought "the lamp will be heated by one side more than another and this could damage the glass". So I put the bulb in a straight position. But then the lamp worked fine except that the lava went up and down in a straight way, instead of circling around, as I'd seen before in another lamps. So I put the bulb back to its original position. But I never opened the bottle nor did any repairing on it. What's wrong with my lamp? My son loves it so I hope you can help me.