Another Reason to Quarantine...

I almost ALWAYS quarantine new fish that I get for an aquarium, but recently, I got a small school of glowlight tetras (5 to be exact) and decided that it was a lot of bother to quarantine them. I decided to add them (after acclimation of course!) directly to the tank with no care taken to make sure they were indeed healthy and disease free. Well, all looked good for about a day and then I lost one of them and then another within a day. I attributed this to stress (not ALL the fish you get will always survive) and didn't think much of it. Then I lost one of my cardinal tetras (one I've had for a good long time) and another glowlight. I decided that medicating the tank with a mild anti-bacterial medication (MelaFix) would be a good idea so I added the correct dose to the tank. The next day things were still not looking good and I had lost one of my black-skirt tetras (I've had them a long time too!) so I decided that moving ALL the remaining fish to a hospital tank for treatment would be the best solution. The remaining fish consisted of 2 cardinal tetras, 2 glowlight tetras, 2 zebra danios, 2 black-skirt tetras, and a platy. Well, now (after a week of being medicated in the new hospital tank) I have lost both glowlight tetras and both cardinal tetras. I was looking last night to try to see WHAT disease this was (because it didn't look parasitic but the bacterial medication clearly wasn't working) and discovered, to my horror, that it was likely the dreaded "neon tetra disease", which does NOT only affect neon tetras but any species of tetra. It doesn't affect other fish quite as much, but it can still cause disease in them too. The worst part is... it is not curable and fish become infected by eating on another dead fish (something that is very hard to prevent in aquariums). So, only time will tell if the black-skirt tetras will be OK or not (they're the only remaining tetras and one can only hope that the other fish will NOT be affected). What is the lesson in this??? ALWAYS quarantine your new aquarium fish!