I have a 90 g aquarium with 5 fancy goldfish and a pleco. Yesterday, I woke up and saw that one of my goldfish has white spots on its tail. I read all the symptoms of ich. He seems to be actong just the same, swiming around actively, doesn't grasp for oxygen and seems to be breathing quite fine, active same as usual. Today I notices another white spot on another goldfish. Is it ich? What should I do? Which medication do you recommend. I've had these fish for 3 months already and maintain regular water changes.