What Causes Fungus On Corys?

[Schmill]

Hi all,

Checked on my fry / shrimp tank this morning and noticed this white fungus on the back half of one of my corys.
I have now placed the fish into a floating fry trap into the tank and treated the whole tank with eSHa 2000 to try and fight it. It is also panting like crazy
Is there anything else I can do?
What would have caused this?

EDIT
Ammonia reads 0 ppm
NitrIte reads 0>0.25 ppm (but water is changed daily to compensate)

 

[Inchworm]

Hi Schmill

That looks bad. I suspect it was caused by a bacterial infection. This is not unusual when corys are kept on a pebbled substrate, even though the water parameters are OK. Dirt and uneaten food tends to sift down into it and feed bacteria that can harm the corys.

I suggest you give the tank a good cleaning and add an antibacterial medicine to clear up the problem if it isn't too far advanced.
There are a couple of other things you can also do to make the environment less agreeable to the bacteria. First, lower your temperature to 75 F. if it is above that. Second, be sure there is plenty of movement at the surface so that the water is well oxygenated.

You might also want to consider changing your substrate when this problem is over to prevent it happening again.

 

[minxfishy]

Looks nasty, Im not sure on esha, but I would suggest some pimafix and myxazin as it looks like columnaris to me.

Edit: You have shrimp in there, not sure on their tolerance of those meds, any chance you can remove the infected cories to any tank to treat?

 

[Schmill]

Thanks both, sadly it died around 2hrs later.

Can only have been bacterial I think, it certainly shocked me at the sheer speed of 'infection'.
I had waterchanged, and fed them the night before, counting and checking all the cory's and as many shrimp as I could find and all seemed well. The next morning it looked like that

Well, it freaked me out, I read up and seems there is lots of different views on substrates, but idea that large gravel can trap food / decaying matter in the large gaps between it seemed to make sense to me. So I removed the corys into a tub, did a load of vacs, removed the gravel, vaced again, did several large waterchanges, removed the 'cave' structure, put a more powerful airpump on the sponge filter, (which seems to have increased the flow), and now I have a boring, but easier to clean tank.
I'm just hoping it's now not SO bare that it stresses them out, easier to clean though!

 

[Inchworm]

Hi Schmill,

I'm sorry about your little cory.

Some bacterial infections move fast and some act slower, but once a little one like this gets it, it's usually too late to do much. Often they don't even show symptoms.

Prevention, through keeping the water and bottom clean is usually the best thing to keep this condition to a minimum. Take great care with the bare bottom tank as well. You will find it getting a film on the bottom that needs to be wiped off during your daily water changes. Just rub it with your hand and change some water.

A small layer of sand seems to work best for me on the bottom of fry tanks. All that takes is a stir every week or so to keep the surface broken up.

 

[Schmill]

Well tank & water must have been good as it has been being vac-ed and waterchanged everyday at the moment.
I figured it had to be something in the gravel, hence took it out.
Today I have added a thin layer of sand in the tank too, so keeping fingers crossed

 

[Inchworm]

Hi Schmill

They look a lot more comfortable in there now, don't they? Look at their sweet little barbels.