Emperor tail blotch

[pinnatus]

My large adult emperor has a large part of his tail fin that looks swollen, maybe an inch in diameter. In certain light it looks red. He is the largest, meanest fish in the tank, so I don't think it is some sort of bite. Doesn't look like fin rot. I have had him for quite a while and just noticed this yesterday.

Anyone have a clue? I have kept marine fish for 41 years now and have not seen this before.

 

[pinnatus]

 

[mattcoug]

Ouch, it looks like it is radiating away from the central spot - looks bacterial to me. I would also be worried about uronema. How big is the tank? Anything wet added recently?

 

[pinnatus]

240 gallons. Last thing added was a harlequin tusk maybe 2-3 weeks ago that previously was in another aquarists tank for > 3 years. The tusk jumped out and passed away after being in my tank about 5 days. Other than that, nothing new for months.

 

[mattcoug]

240 gallons. Last thing added was a harlequin tusk maybe 2-3 weeks ago that previously was in another aquarists tank for > 3 years. The tusk jumped out and passed away after being in my tank about 5 days. Other than that, nothing new for months.

Did they fight? Angles can fight with tail/body thumps so I wonder he tried to hit the tusk and got a rock instead. It would explain the jumping tusk.

 

[pinnatus]

Could be. Also there are two emperors in the tank, so could be them fighting too, though I have never seen them fight. The large emp grunts up a storm though.

 

[pinnatus]

Maybe a Naso tail spike got him.

 

[mattcoug]

At this point I would keep a photo journal to make sure you catch when and if it gets any worse. And get your hospital tank ready for immediate treatment if it does. Have Furan 2, kanamycin, and metronidazole on hand.

 

[tylersarah]

It looks like septicemia to me, I'd feed an antibiotic, erythromycin or kanamycin 3x/day in food (can stay in the reef) as long as its eating, otherwise you'll have to treat the water column in a hospital tank.

 

[pinnatus]

Well, I did nothing, and it seems to have cleared up. Have no idea what it was, but glad it went away.