For the most part yes it is. It's next to impossible to keep ich out of our tanks. It is safe to assume that all of our tanks have ich, we only run into problem when our fish becomes stress. When stressed their immune system will drop and ich will have a chance to take hold. We always see threads of someone with an ich outbreak, but they can't understand why because they haven't had a new introduction of livestock in months or more. Well this is why, it was already there lying dormant.