Racoon butterfly problem, Need help !!!

[barracuda]

Hi all,
I have only 2 fish in my FO tank. Cream Angel and Racoon Butterfly. For already 2 days this fish is swiming on 1 side. The fish is eating well, but this is not his regular behavior. Some info: a week ago my Lion fish is died because of unknown reason. Ammonia, Nitrite, Nitrate an PH are OK. Tank is 37 gal, Cannister biofilter and MERLIN fluidization filter.

 

[mr . salty]

By swimming on one side,do you mean one side of the tank,Or he is swimming sideways instead of upright.If he is swimming sideways,he may have gotten stung by that lionfish.If he is staying to one side of the tank,was the other side of the tank the lionfishes home?? He could be afraid of going into the lions space.

 

[barracuda]

The fish is swiming sideways and it seems to me it cannot control the upright position. What can i do in this case?