Update on sick fish

Question
QUESTION: Hi Lynda,
I'm sad to say that we lost our last Blackskirt Tetra today. Nine fish have died over the past 6 days. All that is left is the bushy nose pleco. Should I continue treating my tank with the Triple Sulfa (just in case)? Or should I put the filter back in the tank? I did a water change today (per the instructions on the Triple Sulfa) and added more of the Triple Sulfa. If he continues to survive whatever is in the tank, how long should I wait til I start adding fish again? And is there any precautions that I should do first?

ANSWER: Hi Pat,
 I would think that it could have be Columnaris, but I'm not sure, since the pleco is doing well.  There has to be a reason to what wiped out your entire tank.  Whatever it was it has to do with bad bacteria in your tank.  If you are positively sure, that you have zero ammonia, zero nitrites, and nitrates were low, then I would think that it was columnais disease that killed them.
Columnaris disease is mostly due to stress.  When one fish is stressed either by another fish attacking, or chasing him all the time, he may get Columnaris.  When he does, all fish in the tank get this terrible disease, and die.  This is another reason why we must always buy fish that get along, even then sometimes we hit a bully.  When you see one fish attacking of chasing another fish, he should be removed.  When fish are suppose to live in groups, we must not ignore this, and buy them in groups of six.   Columnaris quickly kills all the fish in a tank, and the best medication is to act quickly and treat with Kanamycin, combined with Furan-2.  It is very difficult to diagnose, seeing as Columnaris resembles many other diseases.
For now, I would not add any fish, or medication.  Put your carbon  back in, do another 25% water change, siphoning from the bottom, making sure that you rid the tank of uneaten food, and waste.  Wait one week, check your water, do another 25% water change, and have your water checked at the pet store, not only for ammonia, but nitrites, and nitrates also.  If your chemistry is fine, buy one fish, and see if he lives.  If this fish should die, then you must start over.  This means emptying your tank, washing your gravel with bleach, and water in a pail, and rinsing it thoroughly.  Wash the inside of the tank using bleach on a paper towel, and fill the tank up again, using stress coat, and letting your tank run until it is cycled.  I hope you will not have to do this.
You can read all about Columnaris Disease here:
http://www.americanaquariumproducts.com/Columnaris.html
I am truly sorry you lost your fish.  I feel for your son.  I know he must have gotten very attached to these fish.  I don't know what to tell him except that these things happen in the fish world, as it does with us sometimes, when a bad virus is going around.
Lynda

---------- FOLLOW-UP ----------

QUESTION: Hi Lynda,

I have done the water changes as you instructed. I had my water tested for ammonia, nitrates, nitrites and Ph and everything was great. I spoke with the girl at the LFS about what has happened. She suggested that I raise the temperature to 82 and treat with Super Ick Cure by API. I am a little leary about adding anything else to my tank. Especially since all I have left is the bushynose pleco. It says on the package that some scaleless fish are sensitive to the meds and I can't get a straight answer on if the bristlenose is scaleless or not. When he allows me to look at him, everything looks good. There are no shiny things on him and all of his fins look intact. What do you suggest?

Michele

Answer
Hi Michele,
There is no reason to put Super Ick Cure in your tank, or raise the temperature, unless your pleco has Ick.  Plecos are not scaleless.  Never medicate for ick, if the fish does not have ick. Never medicate fish if they are not showing signs of sickness.  The pleco can handle Super ick cure, but I would not use this medication unless the fish was sick.  Let him be, and wait one week to see if anything comes out on him.  It is more dangerous to the fish to medicate him when he is not sick.  
This is what I would do..
No medication unless the fish was sick.
Let him roam around the tank with no fish in it for one week.  (You must have driftwood in your tank for the pleco.  He must have driftwood.  They suck on it, and it is food for them.  To clean the driftwood, rinse it well, and leave it in a pail of water for one week, changing the water everyday so that the tint comes out of it.  Feed your pleco wafers, and sinking shrimp pellets.  They do need food.  Do not rely on a pleco to eat spoiled food that has fallen to the bottom of the tank.  He will not eat it, and cannot survive on algae alone.
After one week, do a 25% water change, and buy one fish.  Wait one week to see if the fish stays healthy.  If all goes well, then you can buy other fish, but remember to add fish slowly...two at a time one week, 25% water changes, add two more, and so on.
I hope this helps.
Lynda