Breeding goldfish develop breed tubercles. These are  little pimples on the gill cover side of the goldfish. Other Cyprinids (carps and minnows) may have them elsewhere. "The sensuous pimples." ;) It would be great if this is all that the things are on the goldfish.

http://www.geocities.com/Tokyo/4468/fishsex.html
http://www.fishpondinfo.com/gfish3.htm

Probably your goldfish do have Ich. In the "Now they tell me!" department, you probably should have stuck with that one goldfish until the aquarium had cycled. That, unless you are adding these bacterial supplements, may take 6-8 weeks, maybe longer in cold water. Please see Cycling here in Immediate Help or just Google cycling an aquarium. Cycling is about the most important thing a new aquarist should learn about. The hobby is doing better, but most of us are still fuzzy about the process when newbies.

That also means that you should have spent a fair amount of money on test kits for ammonia, nitrites and nitrates. That money is probably less than what you might otherwise lose in fish though.

Ich organisms are often in aquarium and pond water, but usually at non-lethal levels. When the fish is/are stressed, often by dirty water and/or a temperature shift - especially a chill - their immune system gets compromised and whammo!

Kudos for treating the water. Your products are European and I wouldn't presume to be familiar with them. Are tap safe and fish safe water conditioners, designed to get chlorine out of the water and to bond ammonia (and chloramine) for a time?

Is disease safe (Interpet Gold) designed to treat Ich? Aquarists may kill more fish than they rescue by using the wrong treatments so it is important that the correct treatment is used for the correct amount of time. You will need to continue to prescribed number of days because it will take a week or two to get all the organisms in the water.

The pump and or filter, unless it is knocking the fish around, is not what caused the stress. Running the filter without any carbon in it could be beneficial, as was the airstone, from the standpoint of aerating the tank. (When the water swirls to the surface, carbon dioxide and a tiny bit of free nitrogen can be shed and some oxygen absorbed. I was surprised to learn that bubbles do little more than move the water.)

Partial water changes during treatment are good. Gravel vacuuming is best because you pull up a lot of the organisms which have just dropped off of the goldfish in cyst form and are about to explode into thousands of critters hunting and recolonizing your goldfish. If you pull out 33% of the water, only replace 1/3 of the medication and 1/3 of whatever quantity of aquarium or marine (not household) salt you put in there. Sometimes we over medicate and over salt if we are not careful.

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One last thing, for your benefit and that of any others reading this, some attacks of Ich seem increasingly resistant to medications and the usual treatments. Diana Walstad, one of the really thoughtful aquarists around, has written an article on treating this kind of Ich and also loaded it to:

http://groups.yahoo.com/group/r_m_l/files/ICH05RML.doc

In addition to that, she has also been one of the very few aquarists in the world to maybe effectively deal with the dreaded fish tuberculosis (again around most tanks, almost always untreatable, and triggered by sloppy maintenance) by installing a UV unit which seems to be destroying the free floating Microbacterium before it can transfer from fish to fish. Some of you may have encountered her plant columns or read her book Ecology of the Planted Aquarium : A Practical Manual and Scientific Treatise for the Home Aquarist.

She has also been a part of a very interesting e-mail discussion, considering the heresy of not doing regular water changes. However the advocates of that, such as Rainbowfish maven Gary Lange, have noted that old tanks of that sort will maintain the current residents, but the water chemistry of that aquarium is so, um..., unique, that new fish, even those painstaking acclimated over hours to the new water, will still die. There is a lot of interesting stuff there, not all of which I would agree with. Some of those folks however have forgotten more about aquarium fish diseases than I will ever know. ;)

See also the Winter Mystery Deaths and discussion in the Immediate Help files for more on why we need water changes.

For more, when there is time, browse and search http://groups.yahoo.com/group/r_m_l/messages