Genocidal fungus

I woke up this morning to see that my black madtom had 3 rather significant white spots on it. I was definately worried and told myself I would get sOme anti ich meds from the pet store immediately after work. When I got home I found it dead in the cOrner of the tank. Covered in Nasty s***. it was not a disease I had ever seen before, it looked like it had been dead for days, weeks even. After doing some research I am reasonably sure that it is an external fungus. I hope it's external... I purchased rid ich plus which also cures external diseases fungus included. My tadpole madtom is showing signs of fungus ness along it's back top fins base. Please come forward if you can offer any advice, any experience, any ideas. I can't let my second and last catfish die to this POS disease.

External parasites are usually an issue because of poor water quality. The fish's immune system and slime coating keep it protected as long as it is healthy. The problem happens when ammonia or nitrite rises above 0 ppm, or when nitrate rises above 40 or 50 ppm. At that point the fish loses the ability to combat infections, and it becomes susceptible to the pathogens that were already present.

Measure your ammonia, nitrite, and nitrate. I bet there's something off there. If it was just one fish it could be that it was old or weak, but two sounds like a problem with water quality.

If your nitrogen is high, then what I would do is to do a 25% water change with dechlorinated water every day until the level (ammonia, nitrite, nitrate) gets back to a safe number. Don't medicate just yet. It's possible that the medicine's side effects could stress the fish, so you should get the water clean first and then see if the fish fails to recover after that.
If, after a few days of clean water, the fish continues to worsen, then yes, add the medicine. It's recommended that you do a water change a day or so after adding the meds, to remove the little buggers that have detached themselves from your fish and are floating in the water column. After you've finished the course of the medication, use some activated carbon or Seachem Purigen® to remove the medicine's decaying molecules.

Edited by EricaWieser, 19 July 2011 - 09:01 PM.

I had already medicated prior to reading your post because of how rapidly the fungus or disease advanced on my black madtom. It was an 8 hour window.

I have also stepped up feeding recently from once, occasionally twice if I forget a day to 2-4 times with various foods to figure out what sort of foods my darters can eat. This seems like a possible, even likely cause of sudden fungus assault.

I would forget the water tests (at least in the short term) and just change a lot of water. As long as the temperature difference isn't too extreme, I personally would change 50-60% of the water immediately, and would recommend repeating that tomorrow. Add medication afterward if you like, but I would caution you against combining the two products without a very clear understanding of what you're doing. It's likely that your fungus medication contains the same ingredient as Rid-Ich, which is a combination of several chemicals, and you may be unintentionally overdosing. That could be especially dangerous if the other product is formalin-based, since the recommended dosage is based on the maximum safe level of oxygen depletion in the water.

Overfeeding could be a contributor.

Sounds like it could be Flexibacter (aka Flavobacterium or Columnaris), a bacteria not a fungus, although it is the cause of "mouth fungus" too. Ich/parasite meds will not cure it. Kanamycin, Cephalexin (Keflex), or Furan meds like Jungle Binox might work. It kills fish fast - not much time to diagnose and treat.

Sounds like it could be Flexibacter (aka Flavobacterium or Columnaris), a bacteria not a fungus, although it is the cause of "mouth fungus" too. Ich/parasite meds will not cure it. Kanamycin, Cephalexin (Keflex), or Furan meds like Jungle Binox might work. It kills fish fast - not much time to diagnose and treat.

If it is bacterial, furan is good stuff. I've had Furan 2 completely solve a couple of the bacterially based disease problems in my tank in the past. It's expensive but worth the money if you're using it right.
Of course, it also wiped out a few of the plant species I had at the time, and it has some significant side effects. Yes, it cured the disease it was supposed to, but at a cost.

The issue here is properly diagnosing the "white spots" you saw. If it's a parasite and you treat it with an antibacterial or an antifungal, then all the medication can do is have its normal side effects on your fish without having any of the beneficial effects. Ditto if it's a fungus or a bacteria and you use an anti-parasite medication.
If medications didn't interact with one another or cause any harmful side effects to the fish, then you could just add the meds for all three types of pathogen and your problem would be solved. But they do interact and they will stress your fish, and fish can and do often die of the compounded stresses you've given them above and beyond the stress of the pathogen on them.

If your tap water is a significantly different pH or hardness than your tank water then you don't want to just do indiscriminate massive water changes because forcing the fish to adapt to drastically different water parameters stresses them, too.

Here are some good diagnostic dichotomous keys:
http://www.fishyfarm..._disorders.html
http://www.fishyfarm...s/bacteria.html

You shouldn't add medication without knowing for sure if you've got a parasite like ich, a bacteria like columnaris, or a fungus. Testing the water for ammonia, nitrite, and nitrate and keeping those levels controlled goes a long way towards helping the fish recover.

Edited by EricaWieser, 21 July 2011 - 01:37 PM.