Yellow Tang and Recurring Infection

[Greg P]

Hi All,
My Yellow Tang has been battling an infection for over a year.
Not knowing what the sex is, I call it a He and I've had Him for about 5 years, spanning 3 tanks - all 48" 75g.
He is named Nibbler due to his way of eating.

I'm stumped and looking for help.

@Jay Hemdal @4FordFamily @Humblefish

So, at the time of the initial infection/open wound, I had not added anything new to the tank for over 2 years, nor had I changed my husbandry or dosing.
Right before deciding to do a tank restart/rebuild, a wound appeared. I transferred all fish to a spare DT and treated with API General Cure before transferring them to the new DT. The wound was looking clear and healing.
The new DT was started with new washed sand and new man-made LR which was treated in a tub for over a month with liquid ammonia. When the LR water was showing less than 1 NO3 it was transferred to the new DT. Next the SPS were transferred to the DT.
July 26/19 I added the fish. 1 each yellow tang, springer's dottyback, starry blenny, coral beauty and PJ cardinal. All with us for years.
pH 7.9-8.2
Alk 8.6
Ca 400
Mag 1350
NO3 2
PO4 0

I went through a round of diatoms and possibly dinos, but not enough snot to write home about. During this time I lost a batch of Trochus snails, so too many toxins for them.

By Sept 30th Nibbler's wound had come back strong enough I decided to put him in QT and treat. The wound was ugly

I treated him in a 20 tall with 2 rounds of Furan-2.
During the initial 2nd round dosing his wound went bright red again, so I stopped the dosing and performed a 75% WC and added carbon to the HOB.
I then performed 75% WCs every 2 days from Oct 9th through Oct 23rd. On Oct 25th his wound was staying clear and the flesh had started to return to a yellow color, so back to the DT he went.

Whether this matters or not;
Feb 19th 2020 I ran Milbemax for 3 weeks for Red Bugs. If the amounts used matter please ask.

By March 29th the wound had again returned so this time I decided to, instead of subjecting Nibbler to another round of meds, dipped him in Methylene Blue tank water @ 3ml/3g for 30 mins, then into the QT he went. I watched him for 2 days.
On April 1st I added Seachem StressGuard @ 5ml/16.5g daily until April 10th 2020.
At this time his wound was clear and I could see the yellow color returning to his wound, and the edges of his wound were smooth, so back to the DT he went.
pH7.9-8.2
Alk 7.7
Ca 415
Mag 1350
K 400
NO3 2
PO4 0.03

By July 2020 the wound had come back, just like the cat in that infuriating song ... it just won't stay gone.

I don't want to keep subjecting the poor dude to QT rounds without results, so this time, I dipped him in a bucket of tank water with MB @ 3ml/3g for 30mins, then in a fresh bucket of DT water with StressGuard @ 1ml/2g for 5 mins, then back to the DT. This made the wound very red.
Since then, the redness comes and goes. Sometimes, first thing in the morning it'll be clear, then as the lights wake up the diatoms or whatever, the wound gets redder and redder.
And some days are better than others.

Whether it's pertinent or not, I sometimes get my own wounds/rashes for no reason, even after washing with soap and water after dealing with tank stuff.
They start as a red spot, then turn into what looks like a rash. Could be the same thing? I don't slop water everywhere yet they show up wherever they want to; wrist, elbow, chest, leg.
I use gloves in the tank, but not when I'm cleaning socks/the skimmer etc.
Waiting for a new one before I go to the doctor for a skin scraping.

Hopefully one of you will have some suggestions.
Thanks for taking the time to read !!

 

[Old Fritz]

It could be that you never completely treated the sore and it got reinfected in the dt. How long did you dose furan-2? I also recommend using kanaplex.

 

[Jay Hemdal Verified Community Expert]

Greg,

I'm completely stumped! Generally, open wounds on fish either heal in about 14 days, or the fish dies due to the severity of the infection or osmotic imbalance due to the breached skin barrier.

I presume the other side of the fish is completely normal?

My first answer to your question about your own skin lesions was that salt is often irritating to people's skin and they can develop sensitivity to repeated contact. I got to thinking some more though - aquariums are filled with a number of types of bacteria that can cause human infections, notably Vibrio. I would wear those elbow length aquarium gloves when handling tank materials. I get terrible reactions to bristle worms - they leave red pustules in my hands that last for months.

Jay Hemdal

 

[Greg P]

It could be that you never completely treated the sore and it got reinfected in the dt. How long did you dose furan-2? I also recommend using kanaplex.

Thanks for taking the time to read.
I don't doubt but rather suspect re-infection. I'm trying to figure out what is the cause as more than 1 kind of treatment/method cleared it in the QT.
The Furan-2 I performed a complete dose schedule then performed a WC. I started a second round of dosing but stopped it as it made the wound extremely red.
I'm in Canada and essentially have no access anymore to most meds.

 

[Greg P]

Greg,

I'm completely stumped! Generally, open wounds on fish either heal in about 14 days, or the fish dies due to the severity of the infection or osmotic imbalance due to the breached skin barrier.

I presume the other side of the fish is completely normal?

My first answer to your question about your own skin lesions was that salt is often irritating to people's skin and they can develop sensitivity to repeated contact. I got to thinking some more though - aquariums are filled with a number of types of bacteria that can cause human infections, notably Vibrio. I would wear those elbow length aquarium gloves when handling tank materials. I get terrible reactions to bristle worms - they leave red pustules in my hands that last for months.

Jay Hemdal

Thanks for trying Jay, and for taking the time to read through it all.

The whole rest of the fish is completely normal.
I'm thinking he wounded himself on an SPS branch during one of his rocket sessions around the tank and that's when this opportunistic infection took hold.

I'm starting to lean towards either Cyano or a Fungal infection being the cause.

I picked up some prescription anti-fungal skin cream for myself yesterday so we'll see how that goes.
If it helps me I'll know what direction to go in with Nibbler.

 

[Greg P]

I'll reiterate this infection will many mornings be completely clear of any red markings.
Then as the day progresses so does the redness.

 

[Jay Hemdal Verified Community Expert]

Greg, I've never heard of cyanobacteria infections of fish. I have seen cyano grow on stonefish, but it was a commensal relationship. External fungal infections are extremely rare in marine fish. We had one fish recently that was confirmed to have a fungal infection (by biopsy) and we cured with with daily 75 ppm formalin dips.

Jay

 

[DSEKULA]

Find this really interesting and hope the fish can be cured. I'm wondering if there might be something else going on here that's lowering the fishes immune system or if this infection had maybe gone internal and isn't being completely wiped out by your antibiotics. its just made not visably there, like when a human dosent fully finish their treatment and the infection comes back? But, I'm very limited on my bacterial treatment knowledge @Humblefish has had some really good posts on the subject so consider this a bump and tag. Good luck!

 

[Privateye]

I might be too late to the party, but it looks like an external bacterial infection to me, which caused an ulcer. I'd to a 20 minute bath with 2-2.5 ml of hydrogen peroxide per gallon. Use a lid - some fish jump.

Alternatively, you can go with something like this:

https://pentairaes.com/tricide-neor.html

Or if you're bold enough to handle a tang, I've heard of people using neosporin. Not sure what the residual would do to the biofilter though.