air bubbles in the lava

[Diin]

hi everyone. i have an issue with one of my lamps.. there appears to be an air bubble in one of my lava blobs. how does one go about fixing that?

and a simple honest question, as i dont know too much about lamps. there is always some goo stuck at the top of my lamp and doesnt join the rest of the goo.. is this normal?

[Diin]

i will get pics posted as soon as possible. i need to locate my camera.
the one with the air bubble is a "volcanic lava lamp" im guessing its a knockoff haha