I 100% agree with Ihoy. If they send you an email that they have 1 fish, it is just as likely to be gone as if they didn't! Maybe even more likely! Furthermore, if you are looking for a fish, check the divers den page. If you are checking your email, why not just check the page? The email inventory works for the other livestock because it is more than just one fish. In divers den, it is only one animal.