[Edit] Cardinal tetras - more illnesses???

squishyfishy Member Posts: 10
edited May 2018 in Emergency Room


I have fairly new 2 cardinal tetras that seem to have fallen ill but with different symptoms. My initial thought was injury (Cardinal 1 looked like it was getting better but then looked like it started to flare up again) but I don't really want to take any chances and risk more tetras getting ill so I moved them into a quarantine tank today.

The symptoms

- Cardinal 1: Potential Popeye(?) / cloudy'ish membrane over the right eye.
(The eye isn't really bulging out of the eye socket like typical pop eye from what I've seen on the net).
- Cardinal 2: Somewhat small cloudy mass on right fin.
(Noticed this one a couple of days after cardinal A but couldve already had just did not see it)
- Cardinal 3: Wonky spine (more info in later post)
- Cardinal 4: Loss of scales (more info in later post)
- Cardinal 5: White spot on pupil of eye

Any Medications you've tried

- Tetracycline Hydrochloride tablets (didn't improve either symptoms)

Tank Details

We've had this tank for AGES but have just "revived" the tank early this year.
- 200 Litres
- 20-30% water change every week
- Tank mates: A lost of Guppies, 1x Sucking catfish, 2x very new dwarf gouramis and another 13x cardinals

Test Results

- PH: 7.1
- GH: 100
- KH: 100
- Nitrates: 20
- Ammonia/Nitrites: 0


  • Frayk
    Frayk Member Posts: 1,009
    Sounds like a fungal attack, could be wrong.
    Pimafix and Melafix, 90% water change, increase temp by 2-3 degrees and increase aeration.
  • squishyfishy
    squishyfishy Member Posts: 10
    I've looked online and it seems the tetracycline medication I'm currently using is specifically used for bacterial and doesn't look like it works for fungal infection.

    I might give it a bit more time and see if there's any improvement.

    I'm just hoping it's not something more sinister where I need to worry about my main aquarium...
  • squishyfishy
    squishyfishy Member Posts: 10
    edited May 2018

    What is happening?!? :(

    Below image of cardinal tetra 3 has bent spine. Had it since I bought it. Does not look like it's gotten worse since. However the white line on the tail is new...

    Below images of another cardinal tetra 4 which looks like its lost scales or something. Was not like this when I bought them in the beginning.

    I'm so confused as to why I have 5 cardinal tetras now displaying all different symptoms.
    I've even managed to drop the nitrate in my tank from 40 to 10-20. I think I got myself a dodgy bunch...
  • Bob
    Bob Member, Classifieds Posts: 708
    Hi Squishyfishy,

    I was considering plistophora, “neon disease” when you first posted but this is much more common in neons rather than cardinals. Looking at your latest pics that may well be what you have though and that’s not good news.

    High mortality rate, sometimes responds tp treatment with methylene blue but not always. Methylene blue itself needs to be used with caution also. I did use it to treat a tank once, not for plistophora, but I did have neons and from memory worked a half dose and half exposure time for them.

    Good luck,

  • squishyfishy
    squishyfishy Member Posts: 10
    Thanks for the response Bob.

    I had a look in what you mentioned and I can see why you might think it's that but it seems to have a different kind of patchiness which is probably hard to see in my shocking photo quality (so hard to get a good shot when they're on the move).

    I've since moved him into the quarantine tank just to be sure.
  • squishyfishy
    squishyfishy Member Posts: 10
    Poor guy was struggling so I thought it was best to put it out of it's misery and ended up getting much clearer photos to what was happening. I still have no idea what they are...

  • Heintz.G
    Heintz.G Moderator Posts: 1,367
    Hi Squishy,

    If it's the white worms you're referring to it looks to be Anchor worms.

    Here's some Google pics to compare, https://www.google.com.au/search?q=anchor+worms+tetra&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiZ3fTkyrvbAhUGP6wKHWn7AIUQsAQIJg&biw=1613&bih=952
    Sometimes when I reflect back on all the beer I drink I feel ashamed. Then I look into the glass and think about the workers in the brewery and all of their hopes & dreams.
  • squishyfishy
    squishyfishy Member Posts: 10
    Hey Heintz.G

    Yeah they seem to be the closest thing but the worms on my cardinals are fully stuck to the fish (possibly entirely tucked under the scales) and don't seem to 'hang' off the fish which from my understanding is a typical trait of an anchor worm?
  • Bob
    Bob Member, Classifieds Posts: 708
    Looking at those pics I think I would agree with Heintz. The other potential would be “fluke” but not convinced on the evidence.