Tiger Barb going vertical

[mensign]

I have a green tiger barb who seems to really enjoy staying still while in a vertical position, most of the time by the heater. the water temp is within the appropriate range, so why do they do this?

 

[chunksofpoooo]

id hate to suggest it, but he might be dying. Often when a tank isnt cycled the ammonia and nitrites do a considerable amount of damage to a fish's swim bladder. This is only a suggestion, i hope im wrong, im only a newb, so lets hope i am

anyone: this is where you correct me