Silver Arowana has a LARGE quarter size dark black spot

[havapyro2]

the Arowana I worte previously about that is acting all frenzyed now has a large black spot that just developed

its on top of its back parallel to its gills..not aplsce where it would have hit its self in the tank..anyone know what this might be
I am thinking its a cancer from everything i have read.. not good thats for sure..still not eating
think i am going to lose it soon..

 

[Bderick67]

can't say for sure without a pic. But it sounds like a typical desciption for a lost scale.