Clownfish with fin rot?

[Fish Keeper82]

What would be the possible causes of fin rot? i have a black ocellaris that his tail fin has some damage.
i have in the tank a smaller ocellaris clownfish, 1 blue tang, and a green chromis. I've never noticed any aggression between fishes. I watch them pretty closely but i guess there is always that chance.
First sight of fin damage was about a week ago. And didn't see much change since today. Today i noticed was a bit worse.

I should add the black ocellaris has been in my tank about 3 months now.and went through a month quarantine before.
attached is the best picture i was able to take. no other fish have damaged fins.

Tank params
Ammonia 0
Nitrate 1ppm
1.026 SG
Calcium 385
Phosphate .02
Magnesium 1300
Alkalinity 9.35
Temp 80.4

 

[Fish Keeper82]

Would ich cause damaged fins?

 

[Cujo13]

Ragged, torn, or missing fins
Research:
a) Fin Rot and Tail Rot (bacterial)
b) Marine Ich (parasite)
c) Ammonia Poisoning in marine fish
d) Uronema (parasite)
e) Brooklynella (parasite)
f) Marine Flukes (parasite)

 

[Cujo13]

How are the clowns acting toward each other? Also, when you say QT for a month are you just talking observation?

 

[Fish Keeper82]

How are the clowns acting toward each other? Also, when you say QT for a month are you just talking observation?

4 rounds of prazi pro
clowns acting fine with each other i have not noticed any aggression at all. If there is some it would be at night but they've been together for 4 months 1 in the qt tank and three in the main.IDK... driving me nuts. Looks like fins just gone no infection or signs of fungus i can see. At night the clowns sleep together but during the day the black clown swims all over the tank orange stays in one spot i doubt the little orange one is biting at night all of the sudden. Other two fish sleep other side of tank in rockwork and don't come out all night.
here is a pic of today.

 

[Deinonych]

Looks like fin nips to me. Fin rot would have a reddish margin around the frayed area and would not be as defined. Very possibly the clowns are just establishing dominance. Mine used to nip at each other when they were younger. As long as they are eating and otherwise acting normal, I would just observe for now.

 

[Fish Keeper82]

Looks like fin nips to me. Fin rot would have a reddish margin around the frayed area and would not be as defined. Very possibly the clowns are just establishing dominance. Mine used to nip at each other when they were younger. As long as they are eating and otherwise acting normal, I would just observe for now.

Both clowns are eating/acting normal just seems odd to me that the smaller one( he is about half the size) would be nipping at the bigger one. Especially after all this time.

There are no reddish or white marks around the fin. It does appear more and more to look like a nip.

 

[ThRoewer]

Looks like a shredded fin. If it's that it will heal in a few days. If it's a disease it will likely get worse.
Any other fish in that tank besides these two?

 

[Fish Keeper82]

All Better

All Better

Still not sure what it was since it got worse before it got better. I suspect it was the green chromis nipping early in the morning since that's when the pods are on the glass and they were competing for them.That's my best guess anyway.
Thanks for the replies