Fire Goby (Firefish) fin question

[phoenix316]

I just bought a firefish about 3 weeks ago, it acts normal and eats the shrimp that i feed the fish (it kind of eats the flakes as well, but not as well).
My question is, when i got the fish the fin on top was a good size, half white and half dark red. Over the past three weeks the white has kind of shruken away, leaving only the dark red. And when i say shruken i mean that it has just kind of melted away, it has not changed color to dark red, it is just not there anymore.
Is this a bad sign or just something that happens.
Any help would be appreciated.

 

[cboyfan2020]

what other fish do you have? Something could be nipping at it.

 

[phoenix316]

1 clown
1 four stripe damsel
1 yellow tail damsel
1 six line wrasse
In a 29 gallon
None of the fish have been aggresive with any of the other fish, and it doesn't look like picking, there are no bite marks.

 

[fshhub]

the only thing that i have seen to affect them , is other tank mates.
and yellow tails although not too aggressive, have bothered ours in the past.

 

[phoenix316]

Any other opinions on this, i will post a picture tomorrow, or later tonight, i have to let the batteries for my camera tonight.

 

[jackson_uk]

Id say the clown done it. My tomato clown done the same to my firefish, took off the majority of its pectoral fins and about half of the dorsal. Just keep an eye on them and try to keep the clown well fed

 

[phoenix316]

I finally got a picture of the fish.
It had a full fin in the begining and it has been slowing going down, but it looks to have stopped lately.

 

[cboyfan2020]

Look Out, there is a leopard behind your tank!!!!!!!!!

 

[phoenix316]

Ha, your just jealous of my wallpaper!