Name: Hasemania nana
We would like to tell you something about our experience with this kind of fish. We bought it just to give a little bit of colour to our aquarium and we found out with great surprise that they are not only very elegant and beautiful, but also merry, fast and social. The Hasemania Nana has given a hint of joy to our fishes and we are sure we will soon buy another couple!
I had two, one took over my tank and terrorized my other fish so I removed it and the chaos repealed. I don't know about your tetras but mine also committed fishy suicide when I isolated it.
I have recently introduced seven silver tips to my community tank and found them to be a menace. They constantly chase and nip the other fish in the tank as well as having singled out one of their own and terrorized it, it now only has one eye and has lost its black stripe.
I have two of these fish, but I started with five. I've had them for four years. They do chase some of the other fish sometimes, but only for a few seconds. They never hurt the other fish either. They're in a 40 liter tank with four cherry barbs right now and I haven't had any problems.
I have a single silver-tip, and it constantly "knocks over" my other fish, swimming past them at full-speed and pushing them to the side. When he's not rubbing elbows, he keeps to himself. He's also been known to occasionally lose the color in his tail and turn nearly transparent, but after a dose of meds he regained full color. Perhaps he needs a friend, but right now I don't want to deal with two.
I have had two Silver-Tipped Tetras for approximately one year. The male tends to be a lot darker than the female, with a darker black patch on the tail. The male is extremely territorial, and spends most of his life chasing the female, whilst the female tends to stick to herself. The male also tends to pick on fish that are the same size as him, Neons and Cherry Barbs etc, and will also chase larger fish such as Head-and-Tail Lights and Pristellas. I have read that they are extremely difficult to breed.