Swordtail Damaged or Rotting Scales

[idossa]

Hi Everyone,

Hoping someone can help identify what is going on with these swordtails.

I noticed about 2-3 weeks ago a white patch on top of one of the swordtails in my tank (almost looks like scales have fallen off). I figured it may have just damaged scales from bumping into the rocks. But over the last couple of weeks, I've noticed the white patch getting larger (see pictures below). What is more concerning is that other fish (2 or 3) are now showing similar symptoms but on the body or tail. Last week, I began treating the whole tank with Melafix and Pimafix with no results (in fact, it looks like its gotten worse).

Ammonia - 0
Nitrite - 0
Nitrate - 20
pH - 7.2

Does anyone know what this could be or how to treat it?

Thanks for your help.

 

[Metalhead88]

How long has this tank been set up?

What other fish are in the tank?

Are you certain on your readings? How was it tested.

It is a bit odd, but if I had to guess, I'd say it's ammonia burn. We can write that off though if ammonia is absolutely zero.

Testing strips are inaccurate. For the most accurate results, use a liquid test kit.

 

[idossa]

How long has this tank been set up?

What other fish are in the tank?

Are you certain on your readings? How was it tested.

It is a bit odd, but if I had to guess, I'd say it's ammonia burn. We can write that off though if ammonia is absolutely zero.

Testing strips are inaccurate. For the most accurate results, use a liquid test kit.

Thank for the quick reply and suggestions.

The tank has been up for about two years now.

I have 8 swordtails and 1 bristlenose pleco in the tank (30 gallon). The bristlenose was the latest addition but has been in the tank for about 6 months.

I've always been using the API Master Test Kit, but just bought another one today in case the one I had wasn't giving the right results (too old?). Also bought a GH/KH test kit.

Just did another check of the water parameters (with the new and old test kits) and got the same results.

Ammonia - 0
Nitrite - 0
Nitrate - 20
pH - 7.2
Temp - 78F
GH - 180
KH - 80

Thanks.

 

[Essjay]

The GH is a bit too low for swordtails, but that should not cause the white patch. At worst, the GH might stress the fish making them more susceptible to disease.
I'm afraid I don't know what the white patch is though.

 

[idossa]

Just a quick update.

I had a chance to visit a local fish store last week to ask them if they had any clue as to what would cause these greyish/white spots on my swordtails.

It was suggested to be columnaris (or livebearers disease?). I hadn't heard of the latter and still not sure if the two are the same (just different names), but was suggested the only treatment would be a high volume of salt, since antibiotics are no longer available in Canada. Luckily while going through my tote of 'fish stuff', I found a bottle of Kanaplex, Focus and Paraguard.

Has anyone had success treating fish with salt, (as this would be preferred over using the antibiotics)? Or should I just start with the Kanaplex treatment?

The local fish store suggested to begin dosing with 1 Tbps of salt per 5 gallons and then increasing it by 1 Tbps per 5 gallons very couple of days until I reach a maximum of 1Tbps per gallon.

Thanks again for all the help.

 

[idossa]

Another quick update.

I began treating the swordtails in my tank with salt earlier this week, as per the instructions in my previous post. I've reached a dosage of 2 Tbps per 5 gallons today. I've noticed a minor improvement in the damaged scales (look like they are healing) and haven't seen any new problem areas.

Will stop adding any more salt to the tank and monitor for the next few days.

One side-effect I've noticed today is that the fish seem very jumpy and dart around the bottom of the tank (almost like they've been startled/scared). This happened when feeding, which was a little odd as they usually come right up to the top when they see me adding food. Will continue to monitor.

Thanks.

 

[idossa]

Last update.

Stopped adding salt as of January 10th and did two, ~30% water changes (and cleaned HOB filter) since then.

No new signs of any damaged (greyish-white) scales. All fish which were affected seem to be healing fairly well (almost not noticeable). Fish have started to act a little more normal when I approach the tank, although they still seem a little startled if I return while they're eating. Hopefully this goes away on its own over time.

Wanted to leave this note, if anyone else may come across this issue.

Thanks.