Thank you for helping us! We appreciate it!Just reading a little more, you might be a little more concerned if it is completely blocking his mouth. Is his mouth open at all? Does it look like his gills are moving more rapidly?
I might have spoken too soon, I’m not sure he will be able to get enough oxygen without water being able to pass through his mouth and over his gills... apparently the amount of water movement needed to meet oxygen requirements is pretty incredible.
Always learning in this hobby...