The white fungus was probably cause by some damage to its scales such as rubbing during breeding which allowed the fungus to get started.

It will only spread to the other fish if they have damaged scales too.

If it was due to breeding, removing her will help her heal since she will not be chased by the males.

Actually it shouldn't spead to other fish directly. But the conditions that caused it in this fish might effect others as well.

Try treating with Malachite Green. It is an anti fungal. You can treat the entire pond or remove the fish and treat in a QT. Proform C has Malachite Green in it, so does Rid-Ich. Both products are pretty easy to find.

I work at Petsmart, so I will go in and check today. I am worried as we've never had any problems with our fish! We have 3 koi and maybe 5 goldfish.
My dad has been re-doing the waterfall, maybe this stressed the little one out?
I found a few products online:

http://www.petsmart.com/global/product_detail.jsp?PRODUCT%3C%3Eprd_id=845524441775168&FOLDER%3C%3Efolder_id=2534374302030162&ASSORTMENT%3C%3East_id=2534374302023693&bmUID=1179172667298&itemNo=5&In=Fish&N=2030162&Ne=2

http://www.petsmart.com/global/product_detail.jsp?PRODUCT%3C%3Eprd_id=845524441775156&FOLDER%3C%3Efolder_id=2534374302030162&ASSORTMENT%3C%3East_id=2534374302023693&bmUID=1179172667245&itemNo=4&In=Fish&N=2030162&Ne=2

http://www.junglepond.com/details.asp?item=PC117-20

http://www.junglepond.com/details.asp?item=PF165

Any luck with these?

not sure what the jungle pond products are. And the links on the petsmart websute were too long to paste. but petsmart does carry rid ich so if thats what you were linking too then thats what you want. Rid-ich is basically just a mix of Malachite Green and Formalin. Same basic product and Proform C but Proform C is a bit cheaper I think and treats more gallons.

and these products won't hurt frogs, tadpoles, snails or plants?
I hate messing with the water as its been so good up until now.
We didn't even put the frogs in, they came on their own.

Its only dangerous for parasites and fungus. I have never heard of Proform C or Rid Ich harming any sort of plant, fish or reptile. But if you are worried about it, remove the sick fish to a QT tank and treat there.

But I have in the past done a triple dose with Proform C and had no problems with the fish. It's actually a pretty mild product.

Well, off to see what Ican find. Wish me luck!

do a web search for Proform C...you will find dozens of places selling it.

Nowhere in the area had Proform C, but someone recommended IchNix, which contains Malachite Green.

never heard of it, but probably the same thing.

Actually it is ICH NOX. I have the Quaratine all set up but can't catch the fish! Alas!

The fungus your fish probably has is called Saprolegnia, or SAP for short. SAP is a fungus that lives in most ponds (in low levels) and prefers cooler water. It is an opportunistic fungus, attacking decaying organisims (like uneaten fish food) and sick fish (sores, ragged fins, etc). It anchors in to the fish's skin and releases toxins which make the fish very sick. To treat it, I suggest the following:

1. Clean up the pond to reduce SAP levels. Remove any buildup in the bottom and clean the filters.

2. Remove the sick fish. Sedate him by adding 8 drops of clove oil to a gallon of water. Mix well and add fish. After about 5 minutes, he will roll over and can be handled easily. remove him from the water and place him on a piece of plastic bubble wrap. Put some saran wrap over his eyes so they don't dry out.

3. Wear gloves....some of the chemicals we use on our fish are not terribly safe for human contact. Working quickly, gently scrub the sap off with a q-tip and peroxide. Do not let any peroxide get in his gills or eyes. Do not be shocked if the skin comes off witht he sap as sap damaged skin tissues and this is common.

4. Dab a little malachite green directly on the area that was affected by SAP. Again....be careful it does not get in his eyes or gills. Give the malachite green a few seconds to dry and sprinkle denture powder on top to seal the area up.

5. Place the sick fish in a heated hospital tank. He has damaged skin and the other fish may pick at the area. Place him in a well aerated area until he recovers from from the sedation. He should be swimming again within about 6 minutes. Make sure you don't keep him out of the water under sedation for more than a couple of minutes.

6. Keep a close eye out for reoccurance. SAP is very persistant.

good advice ccoombs!

sedating is not as difficult as one would think. Kinda scary the first time you try it. a couple tips on sedating the fish. mix the clove oil in a separate bottle with water and shake like mad before adding it to the bowl. I like to use a clean snapple bottle but anything like that will work. Clove oil doesn't like to mix with water and needs a lot of agitation.

also, I am a big fan of a terry cloth towel wrapped in a trash bag as the cushion for laying the fish on. You can form it with a low spot in the center so the fish doesn't slide around.

Be VERY careful with the hydrogen peroxide. If it gets in the gills that's pretty much all she wrote. It's highly effective for treating topical wounds, you just need to pay attention to what you are doing.

Not sure if you want to do all this for one little goldfish unless it has a lot of sentimental value, but it can also be a good learning experience.

Good idea about the towel in the garbage bag trick. I'll have to try that one. I use an egg whisk to mix the clove oil in with the water. It works quite well!

This is probably not a valuable fish, but like surfhead said, it could be a good learning experience. Sedating a fish is very easy to do. If a fish is very sick, sedating him might finish him off, but I have never personally seen that happen and I have sedated quite a few fish in the past. Learn how to sedate and treat this little guy. Even if he does not pull through, the lessons you learned are valuable and might make it possible to save the next one that needs medical attention.