[billsreef]

Keep in mind that the life cycle of ich (Cryptocaryon irritans) is to fall off the fish (giving the appearance of the fish getting better) and reproducing in the substrate. After this it reinfects the fish even worse several days later (about 7-10 days). Hence any treatment regimen you try needs to run several weeks, at least 4 preferably. The dark spots are depigmention due to the attachment of the ich. Usually with clean water and good diet they will clear up soon after the ich is cured.