OK, will put in my .02. I have used AF for years and never killed a flea, let alone my fish. Usually though I under dose slightly. But I'm VERY CAREFUL about mixing the stuff and using it exactly as the label instructs. I have only used it for string algae because if it looks like the pond is going green, then I filter, filter, filter. So there ya go folks. What works for one person may not work for another. But it sounds like Dsep is doing what she should if her fish are healthy and the SA is under control. And no, you won't need the AF now that it is colder. I only use it for a couple of weeks and when the SA slows down, then I stop.