lionfish dorsal fin rot vs triggerfish eating dorsal fin covering

[jcharrsn27]

Not sure if the pic is very clear or not, when you click on the picture it is easier to see. We got this volitans lionfish about a week ago he eats well and yesterday noticed the feather like covering on the dorsal fins is disappearing. Tankmates are a blue throat triggerfish, a niger triggerfish, and a damsel(he is still around from tank cycling). LFS guy says the triggers are eating the fins off of him but I have yet to catch them do it or it is fin rot. Any knowledge or experience as to the cause of this would be appreciated and suggestions to remedy the issue are welcomed.

 

[jcharrsn27]

This pic may be better. I need to get a better camera than my phone for sure!!!

 

[KLR]

Ive read triggers will pick at the long fins of fish,particurarly lionfishes. But ive never kept both fish in the same tank myself.