Bubbles
Bubbles is a Yellow Tang fish.
they're called "lantern' fish so they pretty much do produce their own light
yes bubbles help bring air to the fish and keep the water moving
Yep, it's called milt.
they have an organ called a swim bladder. it is a buoyancy device
Go to the store and ask for a "bubbler", literally just a little device that makes bubbles. The kind/quantity you need depends on the size of your tank & number of fish.
fish
You are supposed to have bubbles in your fish tank or else your fish will die because they don't have enough oxygen.
Then your filter is not on.
Bubbles
Are you sure they're bubbles and not eggs? If they're bubbles the it is just from your filter putting bubbles in the water.