What killed my flagfin?

[Ben jammin]

I have a flagfin angel that I added to my DT a few weeks ago. He's been eating great and has always appeared very healthy - great fish. Two nights ago I noticed a small white blemish on his left side. Didn't look like anything in particular so I figured I'd keep an eye on it. By last night it had developed into a large white ulcer. He was still eating, but he did seem a little less active later in the evening. I was definitely worried and planned to post about it today. Too late - this morning he was dead. I am so bummed out.

Here's a pic of him from last night:

Any idea what this might have been? Is there any treatment I can/should do in my tank as a preventative? I am concerned about what may be in my tank. I have a large FOWLR, and while I don't see any symptoms on any of my other fish I am worried it could spread.

Also, I have a red coris wrasse waiting for me in quarantine at my LFS right now. I was planning to add him this weekend but I'm concerned that maybe I should wait?

Any insight would be appreciated. Thanks.

 

[Humblefish]

Looks like a bacterial disease/infection. They come in two varieties - gram positive & gram negative. The gram positive ones are usually pretty mild, and in most cases a fish's natural immune system can take care of it without any intervention on your part. Of course, soaking fish food in vitamin supplements (to boost the immune system) always helps. Gram negative infections are very different in nature & very deadly - most can kill a fish within 72 hrs unless treated promptly with a broad spectrum antibiotic. The problem is it is almost impossible to differentiate between the two without a skin scrape examined under a microscope. Generally speaking; gram positive is more likely with established fish, while gram negative is most often seen on newly acquired fish taken from the ocean. How long have you had the Flagfin?

Whether or not a bacterial disease is contagious is hard to say, so I would hold off adding anymore new fish for awhile to see if any of your established fish show symptoms.

 

[MrDJeep123]

What other fish do you have with the flagfin? I think the cause is a serious territorial dispute with someone. Are there any other signs of this with the other fish?

 

[Ben jammin]

I have a 260 gallon tank with a lot of other fish, but I watch it closely and never saw any territorial disputes involving the flagfin (or any other fish for that matter). I had the flagfin for 2-1/2 weeks. Given that, and how virulent this was, it sounds like it was probably gram negative.

I soak their food daily with Selcon and a couple drops of garlic xtreme. I have seen medicated food called Dr. G's aty LFS. Is it worth using that for a couple weeks as a prophylactic for my other fish? Is there an antibiotic I could treat the tank with that won't kill my bacterial filter?

 

[Humblefish]

I have a 260 gallon tank with a lot of other fish, but I watch it closely and never saw any territorial disputes involving the flagfin (or any other fish for that matter). I had the flagfin for 2-1/2 weeks. Given that, and how virulent this was, it sounds like it was probably gram negative.

I soak their food daily with Selcon and a couple drops of garlic xtreme. I have seen medicated food called Dr. G's aty LFS. Is it worth using that for a couple weeks as a prophylactic for my other fish? Is there an antibiotic I could treat the tank with that won't kill my bacterial filter?

Antibiotics will kill off some of your bio-filter's nitrifying bacteria, but usually not to the point where it no longer works. However, if you have a large fish bio-load I would be careful - or you could see an ammonia spike. The main problem with dosing antibiotics in a DT is negative interaction with corals/inverts.

I've never personally used Dr. G's, but I've read mixed reviews. The "anti-bacterial" formula is what you'd want to use, as that contains kanamycin & metronidazole. Metro is pretty reef safe, but be conservative feeding it with kanamycin (the antibiotic) mixed in. I think most of the negative reviews I've read about it pertains to the "anti-parasitic" formula which contains Chloroquine phosphate - a very bitter tasting med most fish won't eat.

Hopefully whatever this was doesn't spread to any of your other fish. Just sit tight for now and keep a close eye on them.

 

[MrDJeep123]

I have a 260 gallon tank with a lot of other fish, but I watch it closely and never saw any territorial disputes involving the flagfin (or any other fish for that matter). I had the flagfin for 2-1/2 weeks. Given that, and how virulent this was, it sounds like it was probably gram negative.

I soak their food daily with Selcon and a couple drops of garlic xtreme. I have seen medicated food called Dr. G's aty LFS. Is it worth using that for a couple weeks as a prophylactic for my other fish? Is there an antibiotic I could treat the tank with that won't kill my bacterial filter?

Well, to be fair, you aren't at your tank 24/7. The reason I say territorial issue is because you didn't mention of any issues prior to getting it. You mentioned it eating extremely well, it's appearance was overall healthy. Sores don't just open out of nowhere. There is a possibility that something nipped the fish, then it got worse from there with decreased immunity because of stress. That's my reasoning. :nerd: I could be way, way, way off. For what it's worth, sorry about your loss on the fish. Do you quarantine? If not what does your LFS do in regards to that?

 

[Humblefish]

Sores don't just open out of nowhere. There is a possibility that something nipped the fish, then it got worse from there with decreased immunity because of stress. That's my reasoning. :nerd: I could be way, way, way off.

You are right that infection usually needs an "opening" to occur. It can be a cut, bite or even tiny exit wounds left by feeding ich trophonts. If just one harmful bacterium is present in the water, finds that opening, and the fish's immune system is unable to immediately repel... a sore or white film or "fungus" looking growth, etc. means infection has set in. Sometimes a fish's natural immune system is still able to win the war, sometimes not. It mostly comes down to what strain of bacteria is on the opposing side and how healthy your fish's immune system is. Fish with preexisting parasitic infestations (ex. ich) are more vulnerable because their immune systems are already stretched thin as it is. In a lot of cases, it's not ich that kills the fish... but the "secondary" bacterial infection which puts the nail in the coffin.

 

[MrDJeep123]

You are right that infection usually needs an "opening" to occur. It can be a cut, bite or even tiny exit wounds left by feeding ich trophonts. If just one harmful bacterium is present in the water, finds that opening, and the fish's immune system is unable to immediately repel... a sore or white film or "fungus" looking growth, etc. means infection has set in. Sometimes a fish's natural immune system is still able to win the war, sometimes not. It mostly comes down to what strain of bacteria is on the opposing side and how healthy your fish's immune system is. Fish with preexisting parasitic infestations (ex. ich) are more vulnerable because their immune systems are already stretched thin as it is. In a lot of cases, it's not ich that kills the fish... but the "secondary" bacterial infection which puts the nail in the coffin.

You have made a very valid point. And you are right that all it takes is the tiniest bit of bad bacteria...I was a bit focused on the cause of the sore. I had blinders on. :israel:

 

[Ben jammin]

I appreciate the insights, and the questions. To clarify a few things - my tank is a FOWLR and I have no cleanup crew or other inverts to worry about (other than a few small crabs and hermits that survived doses of cupramine and prazi several months ago, not to mention my wrasses, triggers and other fish that should have eaten them long before now).

It's true I am not at my tank all day, and I have observed minor instances of aggression but nothing serious. My PBT would occassionally chase the flagfin around the tank briefly but only chase - I never saw it use its scalpel on him, and I know for a fact that the flagfin was "clean" and free of cuts or wounds until this struck. I observe all my fish closely every day, and I especially loved looking at the subtle marbling on his sides. It was Monday night that the lesion first appeared, and by Wednesday morning he was dead. So, who knows what really allowed the infection to strike, but none of the obvious signs were apparent.

My LFS is pretty good - the run copper and prazi in their system, and also do FW dips, though I'm not sure they do them on angels, and I know copper and prazi kill parasites not bacteria. What's particularly strange/frustrating though is that flagfins are known to be difficult to get feeding. This was one was eating like a pig from day one at the store. I saw him after he'd been there for 3-4 days and grabbed him because he was eating so well and appeared so healthy. He acclimated to my tank like a champ and had been doing great ever since.

I'll be going home shortly and will check the tank. Hopefully no other fish will show signs and I'll just keep a close eye. I do have a heavy bioload, but I'm more than willing to treat the tank or try Dr. G's if necessary. I'd rather do that than lose a lot of fish. Most of my other fish have been with me for months or a year and have been very hardy.