Strange "whitehead" on Pearlscale Goldfish?

Was feeding my fish this AM and noticed a strange white bump on the side of my pearlscale. Looks almost close to when you have a white head (pimple).

Only other things I've ever seen that looked close to that was anchor worm a couple years ago, but I haven't added any fish to this tank in a long time.

Wondering whether it's just a scrape or something. May feed some anti-bacteria meds for a few days and hold on to an eye on it. Do some water changes... Thing that sucks is I'm going out of town Thursday for a week. Bad timing.

Only thing that have changed recently is using Amquel to dechlorinate water instead of Prime (store was out).

Pearlscales enjoy some sort of calcium deposit under their scales, I wonder if this is what I'm seeing somehow.

Fish: One pearlscale and 2 ryukins
Tank: 65 gallon
Filter: One Fluval 205 canister and one Fluval 404 canister
Water: 30-50% water amend every 6-10 days
It's probably ICK.

Go to your pet store, they have water treatment in that.
sounds resembling a fungus to me I cant remember the name but it starts as a small white spot then will end up covering the in one piece fish and killing it.
Answers:    Number one, thank you for not overcrowding your tank. And for switching to AmQuel (that was a good thing) It is closely better than prime. I suggest you also start using NovAqua (made my the same company as AmQuel) in rider, it improves water quality, provides fish near an essential slime coat, prevents stress, and prevents disease.

Your fish probably has Ich, a common fish parasite. It is better to treat it impulsive on, otherwise it will take your fish' life, so go to the store and buy QuIckCure medication at once. Also, unless you already have it, buy aquarium salt crystals. Putting this in your river will improve water quality and it is pious for freshwater fish especially as a disease preventative. Lastly, raising the temperature to the big 70s will help the white cysts grow faster, and although this sounds like a bas thing, it is not: you want them to grow so they will drop stale your fish and become free swimming. This is could because that is when they can be killed by the QuIck Cure medication. For the QuIck Cure: Put in around 60 drops every day (because you have a huge tank) and before treating do a 30% hose change daily for the next week. DO NOT OVERDOSE. Before medicating, embezzle out the carbon in your filter.

After cured, from now on only do 30% hose down changes weekly, no more than that, and continue using aquarium salt.

Good luck!
sounds like an anchorworm or ick
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