The Neon Tetra is very similar to the Cardinal Tetra. How do you tell the difference between a Neon Tetra and a Cardinal Tetra? The difference lies in the coloration. Cardinal Tetras hold their coloration from the tip of the mouth to the end of the tail. Neon Tetras have a small break in the red lining that runs down their side. Their belly is often a white-silver coloration. Neon Tetras will not grow as large, often maximum size is less than 1″. Neon Tetras are extremely cheap and can be bought at almost any pet store or LFS. For this reason they are the best budget solution when a school of fish is required. Purchasing 50-100 in a very large aquarium will make for a stunning display.
Pseudomugil: from the Ancient Greek ψευδής (pseudes), meaning ..
During the night, when the fish is resting in a sheltered place, the sparkling colours will be turned off and the fish will look dim. If you quickly turn on the lights in the aquarium after a longer period of complete darkness, you might not notice your Neon Tetras at first. If the colouration continues to be dull even after some time in the light, your tetras might be ill or stressed. You might also be keeping them on an inadequate diet.
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The Neon Tetra is often mixed up with the Cardinal Tetra, since they both feature striking red and blue stripes. The Cardinal Tetra is even sometimes referred to as “Red Neon Tetra” in everyday language, even though it is in fact a separate species and not a colour variation of the Neon Tetra. Distinguishing these two species from each other is however not difficult at all if you know what to look for. Under the sparkling blue stripe, you will see a red lateral stripe in both species. If this red strip ends roughly halfway from the nose of the fish, you are looking at a Neon Tetra. If the striping instead continuous much longer, you are looking at a Cardinal Tetra. The name Cardinal Tetra is derived from the long, red robes worn by cardinals and these robes do not end half-way.
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