Had a good look around for this using google etc. and couldn't find whether Ich or Malachite Green treatment has any long term effects on fish. Have a couple of fish in my display tank with a few spots and have dosed slightly under recommended and raised the temperature a couple of degrees. Have treated different tanks before and I caught this very early, dosage in within an hour of the spots becoming visible (Fed them - no spots, did some work, looked and my Chocolate had a few spots), so I shouldn't have any real problems I hope. Fish are all active and feeding currently.
Cheers.
Cheers.