(not from the net!)
Rummy noses are hardy and active. When kept in a planted tank and fed well, they get very bright, red noses and race around the tank together. The more the merrier. I have only had one die on me in the last few years, and it was due to what was most likely an internal parasite that came with the fish. It looked emaciated around the time of its death, even though it ate well. All others have been fine. I think the main cause of death for these fish is probably when people try to keep their water at ideal conditions--all of the fluctuations and chemicals kill them. Like most fish, they enjoy clean water with regular water changes and parameters that vary minimally (pH, hardness, temp.). Don't go trying to lower your pH or some such thing unless you have the means to do so and a good understanding of water chemistry.
I keep a school of 10 rummynoses in a 284 L tank with 10 neons and 5 harlequin rasboras. They are the tightest schoolers out of the group, and are my favorite fish in the tank. It is true that the most crucial point in keeping this fish is the transfer, as they are VERY sensitive and the word hardy does not apply in any situation with these guys. I have found that the most successful acclimation involves putting them in an opaque 20 liter bucket, and setting them up with a drip siphon from the tank they are to be quarantined in for no less than 3 hours, and then drip acclimated in the same manner after quarantine, to the tank of their final destination.
Personally, I believe that the trick with these little guys is to find a LFS that got in a good shipment of them. I work at a "mom and pop" FS and we have had 3 straight shipments at a time where they were all decimated by disease within 48 hours. Just make sure you get good stock before you purchase them.
When these tetras are fed traditional flake foods, they do not eat with excitement or enthusiasm. Just treat them to artemia, even freeze dried, or other aquatic insects, shrimps and worms in order to witness a feeding frenzy.
I was shocked when I saw the recommended tank size for Rummy Nose Tetra. This fish must be kept in groups of a minimum of 10 fish (better 30 and more). Tank size should be at least 200 liters. These fish are very very active swimmers. I'm keeping a group of about 60 individuals in a 672 liter tank. It is spectacular to see them swimming in large groups in a large enough tank. In a 40 liter tank they'll lose their specific behavior and will just hang around.
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