I can't get rid of ich in my 90 gallon. My 2 tiger oscars got ich all over them, so i put them in my quarantine tank and healed them back to better health. My jack dempsey did not contract ich while being in the same tank with the oscars. I recently added a green terror into the 90 gallon and now he has ich all over him, while the jack dempsey doesn't have a single spec. I have treated the water multiple times without any luck of ridding it from my tank. I feel like i've tried everything. Please help before my fish can't handle it anymore.