You would have to sit there non-stop, waiting for the cooldown to sell a little bit of fert. It's just not worth it for a bit of scrap when other methods would be more profitable. If that's still a problem maybe make instances for cooldown if thats possible? I think at that point, if you're willing to sit there all day to sell fert, good luck to you. You won't be making millions of scrap from it a week, that's for sure