What is White Cottony Stuff on a Fish?

My friend has 1 guppy
she was in a tank with another guppy that has sadly expired...
the remaining guppy is now sitting idle on the top left hand side of the tank with a white cottony substance that appears to be growing on his nose...does a fish have a nose? she says that there is also some of this white cottony substance inside the tank itself......
what is this?

Disease and pestilence

I told her I did not think this was good news at all
she will likely also lose her....
anything she can do?

whatever this is would only be contagious to other fish correct? my girlfriend sees the word pestilence and is now very nervous

Some stuff can transfer to people, if you see disease in the tank use gloves

White cottony stuff is not a good thing to see. It is likely she will lose the fish. Small fish like a guppy are not likely to bounce back from that. Is this the only fish left in the tank? If so, treat the tank and don't add any more fish for a while. Don't know how long it takes for something like that to get out of the system. As for using gloves, don't be paranoid, but definitely take precautions. I try to use gloves when I have a sore or cut on my hands, but good aquarium gloves are hard to find. Good luck to your friend.

thank you
my girlfriend is panicking
I am trying to get a photo of tank and fish to post....

and yes one little guppy in a 10 gallon tank all by herself

Here are some pictures she sent, you can see the cottony stuff better on the first picture.

The white cottony stuff attached to the filter looks like what Hippa had on his tail, although for him, it was some kind of combo of fungus and fin-rot as, when the white stuff detached, it took his tail with it. I've never heard of any kind of fungus/parasite growing on inanimate aquarium parts...I thought they would have to be on a living host? Can anyone clarify that for me...I am always learning!

Did she mention if it was just on the fish and the filter (i.e. maybe some detached and got stuck on the intake?), or is it attached to the decorations and/or the glass?

Food can and will rot, the feeding regiment may be to blame. One small fish in a tank that size is over feeding waiting to happen. Do a 50% water change right away , and follow up with 25% every two to three days . She may bounce back...

she added a 2nd but it expired...
she has just done a large water change...
thank youx

goldfishbetalover wrote:she added a 2nd but it expired...
she has just done a large water change...
thank youx

I'm guessing that whatever got the second little guy is now attacking this one. I do know that food can rot and look that way for sure - it happened with our two cories in the 10g in the beginning; at first I thought it was a parasite or pest, but quickly realized it was rotting food! In her case, however, it would seem the new fish brought something nasty in with him. I could be wrong, but there seems to be a quick connection

Never know, she could be dealing with a fungus of sorts, as well as some food rot in there...

I think you may be correct
she has been very diligent with daily water changes since hershey 1st showed signs like the 1st guppy had...this is an old issue
the white cottony growth is a new one
she has said that hershey has not eaten in 2 days...no response to food...
even with the daily water changes could the food still rot
if hershey has fin rot may I also ask if this is deadly? my friend just asked me if I knew.....

Aagh, the site just ate my answer!

Okay, the tank probably has a biofilm, a harmless symptom of a dirty tank. It feeds on overfeeding. Net the fish out, do a 100% water change and refill with a dechlorinated hot and cold mix to the previous temperature. Add 2 tablespoons of kosher, pickling or sea salt per five gallons of water, to stimulate the guppy's immune system. It is salt tolerant, and the irritating salt will make it produce protective body slime- a first line immune defence for fish.

The fish could have old fashioned dirty water fungus (too much food in there), in which case clean will cure it. You could try a pet store fungus cure - they are also good when combined with cleanliness.
It could have columnaris bacteria, a deadly problem. Generally, you don't see that unless the fish was ill at the store, and has only been in your tank for 3 weeks or so, or if you added afish unquarantined in the previous 3-4 weeks.

Everything you describe is gross, but it won't bother a human. If I had a cut, I'd wear gloves. I always do if I have an open wound and an open tank lid at the same time. But there is nothing there that says danger to you.
Poor Ms Guppy is in a tougher corner.

Thank you so much everyone!
I have passed all the helpful information along...
you are all wonderful!...
and yes Gary poor little Ms Guppy is in a tougher corner...hoping she has the strength to pull through and bounce back...
again many thnx

It's not to be critical of your friend - it is incredibly easy to have this happen when you feed one fish, especially if you are new to fishkeeping. We all turn into our grandmothers when we have something to feed.

Plus, it could come from the store - completely out of her control.

thank you Gary...
she is going to do a 100% change of the water...is the aquarium salt alright to use?
and yes I know it sure is easy to overfeed....
I remember when the goldfish 1st came to live with us...they seemed to be hungry all the time and yes with just one so easy to do it without realizing it...
thank you so much again!

Aquarium salt is kosher salt, which is sea salt, which is pickling salt - but at 20 times the price.
I handle all my aquarium salt needs though the bulk barn...

I have aquarium salt here...
thnx Gary!

Update on Hershey
God love her she passed away this morning
I was hopeful that she may bounce back but also somehow knew in my heart she would likely expire....
My girl friend said the white cottony stuff had grown up around her mouth and also on her fin
She said she tried removing it, some of it apparently came off of her tail so she thought she would try her mouth...Little Hershey was very lucky to have my friend taking care of her...now both her heart and her tank are empty
Thanks everyone for your support!

At the end of this sad story, there is a piece of info I either missed or that wasn't stated. Knowing it would help in figuring out the disease, because who knows when the forum will be asked again about something similar?

How long had she had the fish in the tank?

she was originally in a 5.5 gallon...she then upgraded to the 10 gallon...
I have lost track of time so will need to double check with her re the time frame
not very long though
in total perhaps 4 weeks....maybe a little longer but I don't think so.....

I was thinking cotton mouth disease. But I will be simpler and throw this answer.

My guess is a fungus based upon the structure. It makes sense that fungus growth will occur on uneaten food flakes, as well as diseased tissue. Same fungus saprophyte which occurs in the natural fauna of tank ecosystem. I think there was a loss of balance somewhere; either too much feeding, or a weakened fish but not sure which caused which. Under the microscope you would be able to discern the structure; the clue is the cottony growth.

Fungus in humans is NOT the same as fungus in plants and animals. In general transmission does not occur primarily due to temperature and the pH of our bodies.

There are other concerns and uses for fungus : there are natural toxins excreted, for example, a potato fungus was found to have a circle of non-growth around it. Scientists isolated the fungus and found the toxin, later to be derived penicillin. Other plant fungi have derivatives of their culture : antibiotics are well known (ending in "...cillin" like penicillin, ampicillin and "...mycin" as in streptomycin) as well as in treating cancer, as in mitomycin and bleomycin.

In general a balanced tank with good tank hygiene, proper feeding habits, and healthy fish will explain a lot. We will see so many interesting things in the world of aquariums, not all bad. In this case, the natural saprophyte which usually breaks down food and dead plant matter, could have also been attached to the fish.

Be sure to thoroughly clean everything that was in that tank and the tank itself.