Simple q regarding neons

IMO, they'll school until the cardinals are larger than the neons, then they won't stick together as much. Neons tend not to school very well anyway--too many years of being farm bred.

They are two different species. The cardinal is Cheirodoni axeirodi or Paracheirodon axeirodi, depending on which book you read. The neons are Paracheirodon innesi. (These names may have changed.) If you just had one of one species and 5 of the other the loner would join up rather than be alone. I once had 8 of each and they formed two different schools although every now and then some of the members of one could be found with the others, but only for a little while.
Go for the cardinals and let the neons go. They are, IMO, hardier.

my neons have started schooling alot more often since I was forced to switch to a 50G long tank
And, to that point, I have noticed that neons school more often when the tank is long, vs wide.
Prolly some sorta science behind it I'm sure

I have a 55 that I have neons, cardinals, glowlights, bloodfins, greenfires, von rio's, lemons and had black neons and rummynose tetras all together. I also had some serpaes but they got moved to a different tank. Most all the tetras intermingled with no real "game plan" as to where or who they were with. I have no aggressive fish in the tank other than some sailfin mollies that flare at eachother when trying to mate so I guess with no fear, the tetras don't bother to school. My current group of neons and cardinals were all added at the same time. 6 neons and 6 cardinals, they can be found in any number and ratio group at any given time. If they are forced to school (like when I'm cleaning the tank and they get scared), they don't hunt out their own kind, just stick with whoever happens to be close by at the time. Kyle

i think fish being farm bred is a good thing onion girl!

Bear in mind that tetras aren't too smart... I have seen my neons schooling with my white clouds (!) and also seen a lone neon being treated in a seperate tank trying to school with it's neighbors...

Hans--being captive bred can be a good thing, but being farm bred isn't the same. A responsible captive breeding program controls and limits which fish are successful--farm breeding does not. So, fish that are genetically inferior breed with the same success as those that are hardier, and retain more native instincts. This results in a sub-par fish, as can be seen in the poor survival rates and deformities common to neons. If the breeding stock were culled often, this wouldn't be the case.

i get ya :idea2: