Ick is quite distinctive and is best described as looking like white salt crystals on the skin. They don't move independently of the skin. They also cannot be killed at this stage. Only when the cyst bursts and the young parasites, that have been multiplying, are free swimming that medication can do its work. That is why medicating until all the cysts have gone does not cure Ick, the treatment needs be continued for up to two weeks.
Having said that, I have had Ick twice, my own fault for not quarantining new fish, and I only used heat and good tank maintenance to cure it. Raising the heat to about 82f will speed up the cycle of the Ick to suck an extent that the new parasites die before reaching a new host. I believe 85f stops the Ick dead in its tracks but your fish and plants could also suffer badly.
At 80-82f, with daily water changes paying particular attention to the gravel, Ick can be beaten. At higher temperatures oxygen levels tend to fall so extra surface agitation is essential. I raise my filter outlet so it skims the water surface. Dropping the water level an inch or two will work if your filter outlet is at a fixed height.
Losses are sometimes caused by the infestation of Ick on the gills, which are not visible, so there are no guarantees of ridding Ick with no losses of fish.
I would need to have 2 clear weeks without any sign of Ick to believe that it is beaten. You had the breakout about a week ago so you are right to still be vigilant.
Hope that's been of some help and not sent you into the depths of despair. ?
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