Larger or More Aggressive Tetras
The Tetras in this group can be kept with each other, but caution is necessary if putting them with the three species of the Neon group, or with smaller more peaceful tetras. Some tetras slightly larger or more aggressive are: Black Widow, Blind Cave, Buenos Aires, Emperor, Paraguay, Red Eye, and Serpae.
These Tetras are also suitable companions for the small to medium sized Barbs like the Tiger Barb, Gold Barb and Rosy Barb.
As always, be aware of the sizes of your fish and avoid putting large fish with very small ones. For example, the Paraguay Tetra is only in the third group of tetras because it can be a little aggressive, but it is a small fish. You would not want to put a small Paraguay Tetra with as large Rosy Barb.
This is only a short overview of a few of the more common tetras. Before keeping any fish, or other animal, you need to be aware of their needs.
Neon Tetra Group
When people say Tetra, they sometimes mean the Neon Tetra Paracheirodon innesi. This is one of the most popular aquarium fish. The Neon and its near relatives, the Cardinal, Paracheirodon axelrodi and the Green Neon, Paracheirodon simulans are all small fish, subject to predation by larger fish. They are very suitable fish for a community aquarium of small, peaceful fish including the next group of tetras.
Other fish which are suitable companions for the Tetras of the Neon Group include Guppies, Endlers Guppies, Platies and the smaller species of Danio. Smaller specimens of many other species are also suitable companions.
The three species of this group all come from very soft, acidic water. Although they can be acclimatised to Neutral water, avoid letting the water get too alkaline.