Is it finrot? (Angelfish)

[Mae140]

Hey guys.
Today I moved my fish into a 55g aquarium from a 10g (Yes I know the 10g is incredibly small and I shouldn't have used it for the fish I own in the first place).
I set up the 55g yesterday evening and let it run overnight before using the 10g's water to finish filling it before I put the fish in.
One of the fish, a male zebra angel, has frayed fins that I suspect are because of finrot, since the other fish in my tank are not biters (Usually it's the angel doing the chasing).
Besides the angel the fish in the tank are:

- 1 black khuli
- 1 golden dojo
- 1 bala shark

I've had the angel for a few months now, and his fins have been slowly but seemingly progressively getting more and more frayed. The ends of his fins aren't black. The Bala shark however has vibrant full fins, so I'm not sure if he's taking chunks out of the angel behind my back or finrot just doesn't affect him.

So my question is: is the bala shark eating away at my angel or do I have a case of finrot.

Also, if it is finrot I was going to go down to my local pet store tomorrow and pick up some 'Melafix Fish Bacterial Infection Treatment'.
Any advice?

 

[Fishey bricks]

It could be ether, if it is the shark, the angel's fins could get infected. so it is best to quarantine the angel and dose a antibacterial. but if it is fin rot it could be ether fungus or bacterial. fungus form usually looks very frayed, and bacterial will have a more uniform shape. but what ever it is I would recommend quarantining the angelfish.

 

[Mae140]

Alright, thanks.

Sent from my XT907 using Aquarium Advice mobile app

 

[limnologist]

I think the other fish are just eating his fins.