Cardinals vs Neons

[crimsonrain]

and how can I tell which I have? The both look exactly the same to me.

[Yvonne]

The cardinal tetra has more red in it than the neon tetra.  The red in the cardinal starts just behind and under the eye and leads all the way to it's tail, as where the red in a neon starts mid body to the root of it's tail.  As for size and other characteristics, not much of a difference.

[crimsonrain]

wow. i would have never noticed.

[ShieldWolf]

Aside from what Yvonne mentioned about the coloring, cardinals are a wee bit longer & they are more sensitive to water conditions.
Also a bit more expensive and a lil bit harder to find. At least in my experience with looking for them at the lfs.

[ghanz]

Neons are usually slightly fatter at the stomach than cardinals. In my tank, cardinals are much more hardy than neons(10 neons died over 4 months compared to one dead cardinal).
Anyway, both of these fishes(especially neons) can fall sick easily if you got a bad batch like mine.

[UNKDelts]

I have had nothing but bad luck with neon tetras.  I got a few different batches at a several different fish stores, but most would end up dying the first month, and the first batch all went to the swirly gates in the first two days.  They always end up barrel-rolling on me.  I figured it may be the water quality, but I have never lost any other fish out of that tank.  Go figure...

[EricaDwithFish]

Crimsonrain,
    The difference etween neon tetras and cardinal tetras are this: the blue on the neon tetra runs fron the beginning of the tail to the eye and the red reaches from the tail to the middle of the stomach, about. O the cardinal tetra the blue line runs from the tail to the eye wth no space above it, and the red runs all the way beneath it to the eye. So just look at the longer lines to find the cardinal tetra.  :] (check out my pictures to concur with my descriptions.)

                                                  -Erica

[IMKillieKeeper]

Hmm, another major difference between Neons and Cardinals is that Neons prefer cooler waters, high about 76 degrees F.(they spawn at 72), while Cardinals and False Neons (Paracheirodon simulans) like 78-84. This is probably the reason for people who have luck with Cardinals but lose Neons, they put them in too warm a tank. Cardinals and False Neons occur together in a few places, but Neons' and Cardinals' ranges do not cross in the wild.

BTW, the blue line doesn't go to the tail in Cardinals or Neons, it stops at the adipose fin. If you get pale looking "Cardinals" with a blue line that goes right to the base of the tail, that's Paracheirodon simulans. Toughest of the three to maintain and breed.

[EricaDwithFish]

You really can't tell by the water tempature if you're looking at them in a fish store. They could be keeping them at the wrong tempature, so it isn't a very accurate way to tell. (that's just from my point of view)

[Guitarchiq]

Is it true that the cardinals don't spawn well in captivity?
also, what conditions, other than temp, do neons need to spawn?