I bought two beautiful ranchu goldfish from the Central Florida Koi Show back in March. They have been together in a 45 gallon tank (loads of filtration and maintained at ammonia 0, nitrIte 0, nitrAte 10-20), quarantined and going through some basic treatment so they are healthy enough to be in either my pond or my 55 gallon tank. Well, despite my best efforts, they have rapidly begun hemorrhaging over the past two days - septicemia is the only cause I can imagine, and I don't know how it got to this point. I've popped them into a smaller hospital tank now and am giving them antibiotics as recommended by my LFS. I am skeptical that they will make it, which breaks my heart. Now here's my question - I am also raising goldfish fry in a 100 gallon stock tank and need to move some into another tank as they are getting bigger. I do not have an infinite supply of tanks, so I'm hoping I can move some into my 45 gallon for now. However, what do I need to do about making sure it's safe for them. Whatever infected my ranchu was obviously nasty as my typical ParaGuard treatment didn't seem to cure it, and I don't want to see my fry all get horribly sick. The guy at my LFS said I didn't need to worry about it since the bacteria was in the sick fish and not the water and so unless I have my fry around the sick fish, they'll be fine. As a mother of 4 kids, I find that hard to believe. A sick child need merely tap a book with one finger, and the next kid to pick up that book is sick in a span of 12 hours. So I'm keen on advice from you fine, experienced folk.