Dwarf gourami hole in side

[brendan1495]

Noticed last night one of my dwarf gouramis
had a swelling on one side just seen it
today and it seems to have a hole in its
side were the swelling was going to
quarantine tommorow when my quarantine tank
is set up has anyone any ideas
about what this is.

Cheers brendan

 

[Jason7894561230]

Could be hole in the head deseise