Of course I'm right. Go and and a look at a spirit level and you will see why. Look at the texture and size of a spirit level bubble. The size is perfect as is that lovely languid way it settles.
Not have a look at other fish bubbles. Carp bubbles are two big and approach the surface much too quickly. And they pop too soon, avoiding easy collection.
Tench bubbles are much too small and have no value at all.
But the bream. Ah! - such magic exquisitly
shaped bubbles of the right size that stay on the water's surface long enough for the collector to get many in a session.
No wonder that a good bream bubble cost as much as a fiver.