This is a fish that has been kept under very poor care for an extended time. The raised gill covers are usually caused by long term ammonia poisoning and/or cramped quarters and low oxygen. Since all these things are inter-related, it was probably some of each.
-Shane
"My journey is at an end and the tale is told. The reader who has followed so faithfully and so far, they have the right to ask, what do I bring back? It can be summed up in three words. Concentrate upon Uganda."
Winston Churchill, My African Journey
I agree with Shane. You get this gill curl with arowana if the live in poor quality accommodation, i.e. cramped/ bad water quality, it can be operrated on by a vet, they surgically remove part of the operculum, but sometimes the re-growth is not so good.
Hope this helps
Tristan
Not enough tanks, does that sound familiar! L200, L082, L027, L118, L046, Discus & Malawis.