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Here is pics of his gills.

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

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