What is this

the point is, if the poster owned the fish and doesn't know the name, we need to know what the behaviors of the fish were, the diet, and the water needs it had before we can make proper guesses or labels for it.
 
Well, if he doesn't know the name of the fish, he sure didn't know the proper diet and water requirements... It is obviously some speicies of tetra.


I am going out on a limb here and gonna say Charax metae.

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Your fish is a Charax gibbosus (or a very similar Charax sp.), commonly called the glass headstander in the U.S. They are very sturdy, carnivorous South American characins. I've kept a few over the years; the last one I had became quite aggressive (fin-nipping and scale-biting) and I gave him away to a LFS. I had another one many years prior and it was completely peaceful (go figure) and it lived for many years. They have pretty good-sized teeth, from what I recall.

Although called "headstanders," they are quite different from the marble headstanders (Abramites) and spotted headstanders (Chilodus) which tend to eat a lot of vegetation. Typical S.A. "tetra" water conditions; temp in the mid-70s, but will tolerate higher temps, prefers acidic water but can adapt to slightly alkaline. Don't keep with small fish or thread-finned fish. I believe they get about 4"-5" long. I would think they'd be fine with semi-peaceful cichlids (firemouths, uarus, severums), other sturdy characins (silver dollars, anostomus, chalceus), all sorts of South Anerican catfish, etc.
 
The LFS I bought it from called it a Snub Nose. Frome bolvaria.
 
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