Do comets make bubble nests?

Question

i noticed that there were a lot of bubbles on top of my fish tank(at the top)

i was just wandering if male comets make them.

Answer 1

You fish is releasing sperm into the water

Answer 2

Nope. That isn't part of the goldfish behavior. You probably put too much conditioner in the water or have poor water quality. Either way you need to do a water change. : \