Anthia dieing?

[192clark]

I have had a square back Anthia for 6 months. His tail fin has been serrated for a while. His appetite has been great until this last wk. He has barely eaten and is swimming odd. Today he has barely come out of the rock work and is laying up against a rock in an upright position. I have seen no white spots so I am sure its not Ich but I really need help in determining what it is and if I should take him out in order to protect the rest of the fish.

 

[192clark]

I listed my problem in the new to the Hobby forum and only got one response. So I went to the LFS, which is where the know it alls on RC say do not trust. Any of you that have read my first response and knew about tail and fin rot should probably just hang out in the let me blow my own horn forum. Being knew to this hobby I thought this was a place that one could turn to for help. Sorry if my problem was beneath you!
For those that might need help in the future the owner of my LFS said it was tail rot probably caused by other fish nipping at the Anthia. This could cause a site to host a bacterial infection. So the LFS suggested Nitrofurazome. I hope this might help someone that is also new and never encountered the problem. The rest of you, well read my ****ed off mind!