Pajama Cardinal Fin Rot/Erosion

[nop990]

This is my Pajama Cardinal, Fred. I have him in a Fluval Evo with a mild-mannered ocellaris, a barnacle blenny, and a small peaceful CUC. No stinging corals, just those basic orange/green zoas, gsp, and a mushroom. No protein skimmer per se, but I do have a cheap little surface skimmer. Also, no powerheads.

He has had this weird fin erosion for a few months and I can't figure it out. I keep up with my water changes and have dosed with Furan-2 twice. Before his fins started going, my tank almost crashed once but I saved it and haven't seen any problems since. His demeanor has always been fine and he is always begging for food so aside from the obvious problem, he doesn't seem sick. I've been thinking about donating him to my local fish store so he can be put in a larger tank with more of his own kind, but I want him to be cured first. His right fin (not pictured) is almost entirely gone. Any ideas?

My CUC includes all manner of inverts (a snail, a couple hermits, a shrimp, and an urchin) so if possible any medications should be safe for all of those. Thanks in advance!

 

[Jay Hemdal Verified Community Expert]

Hi, welcome to Reef2Reef!

Most fin damage in fish is a result from damage or damage plus secondary bacterial infection. There are cases where fin erosion is a result of dietary issues, but that is pretty rare nowadays.
I wonder - some blennies can be pretty sly, rushing out for a bite, and you may never see it happen.
As far as a treatment, I can’t think of anything that would be safe to use in your main tank.
Jay

 

[vetteguy53081]

This looks like some fin nipping going on here. Jay knows about this simple trick:
Using your cell phone, place it on video mode for about an hour and walk away (must walk away as fish know your presence). Come back and review the video, and you may see something going on here. feeding may help show the activity better.

 

[Poof No Eyebrows]

This looks like some fin nipping going on here. Jay knows about this simple trick:
Using your cell phone, place it on video mode for about an hour and walk away (must walk away as fish know your presence). Come back and review the video, and you may see something going on here. feeding may help show the activity better.

Agree. I have a similar instance and it is exactly as stated, fin nipping.

 

[nop990]

Thanks for the responses everyone, I never even suspected the blenny. I've been focused on the clown because everyone says they can be mean, but she really is as sweet as they come. I'll set up a camera and see if I can catch him in the act. As far as the fins go, I assume with time they will grow back. Is there an average timetable for that? Obviously it depends on the extent of the damage, but just to notice improvement. Also I suppose the only real solution would be to surrender one of them, as I only have and can only afford to care for one saltwater tank atm.

<--- the face of pure evil

 

[exalectric]

Could a peppermint shrimp do this? My pj cardinal is showing the same fin issue, but he and the shrimp are the only inhabitants of this tank.

 

[Jay Hemdal Verified Community Expert]

Could a peppermint shrimp do this? My pj cardinal is showing the same fin issue, but he and the shrimp are the only inhabitants of this tank.

Unlikely, although pj cardinals are pretty slow, peppermint shrimp just aren’t very aggressive.
Jay

 

[exalectric]

Thanks. That's what I was thinking too. Leaning more towards something bacterial but wanted to rule that out first!

Unlikely, although pj cardinals are pretty slow, peppermint shrimp just aren’t very aggressive.
Jay