Tetras

[Freakshow1966]

I am planning on setting up a tank come spring, just researching ahead of the game. One of my favorite fish is the Neon Tetras. Now im seeing green neon tetras, will these school together with normal neons?

 

[Fishguy13]

I am pretty sure they would but you might want someone else's answer as well

 

[howard_hopkinson]

It's not unusual for similar coloured schooling fish to school together. Since green neons & ordinary neons are very similar I think there's a good chance of the schooling together.

 

[Essjay]

In my opinion it is better to have a large shoal of the same species rather than not enough of two species. They'll behave more naturally if there's lots of one species.

 

[seangee]

Technically tetras are not shoaling fish. When they are tightly shoaled it is because they are stressed or insecure. Bigger groups of the same species reduces this as @essjay says. You will often see them hanging out in a group. Again this is more likely to happen when the groups are bigger, especially with different species.

 

[Essjay]

I thought it was the other way round - shoaling means a species that needs to have a number of them while schooling means swimming in tight formation, which applies mainly to marine fish with only a few species of fresh water fish that school under normal circumstances. Most fish will school when threatened.

https://www.fishforums.net/threads/shoaling-or-schooling.103438/

 

[Byron]

That is a very good thread essjay linked. One crucial factor that must be understood is that the "shoaling" is programmed into the species' DNA and if the fish is to be healthy and live a relatively normal life it must have a group of its own in the tank. Regardless of the reasons for shoaling, it is essential.

To the initial question of Paracheirodon innesi (neon tetra) and P. simulans (false or green neon tetra) shoaling... yes, they would likely tend to remain as a shoal but they should never be combined in the same tank because they have very different requirements respecting temperature.

P. innesi is a cooler water species, and temperatures in the range 21-25C/70-77F is as warm as it should be. P. simulans requires more warmth, in the range 23-27C/73-81F and preferably at the upper end for long-term care. The overlap of these two ranges should not be considered as meaning they will be suited together. Long-term and short-term are two very different concepts.

The species P. simulans is sometimes found in the same waters as P. axelrodi (the cardinal tetra), so these are what we term sympatric species. These two species are very closely related, much closer to each other than they are to the "neon" P. innesi in terms of their DNA. P. axelrodi and P. simulans have identical water parameter requirements (GH, KH, pH and tmperature). In temperature however the cardinal tetra P. axelrodi inhabits waters that do not exceed 30°C, and P. simulans lives at temperatures that can surpass 35°C (Campos, et al, 2017). The inference from this is that P. simulans prefers warmth even more than its cousin, and share the tank with species having similar requirements or tolerances, which the neon does not share.

Some years ago I was able to acquire a large group of P. simulans (false/green neon) and I placed these in my Amazon tank which also housed my existing group of P. axelrodi (cardinal). I had had the cardinals for several years by then, and in time they began to die off and my intention was to retain P. simulans going forward. The last three cardinals survived for about two years after the rest of their initial group had departed, and they remained in a relatively tight group with the P. simulans but not with each other. From that I think we can adduce that they were content being among their very close cousins as much as having been among their own species. There was never any sign of trouble, as can sometimes occur when a shoaling species becomes reduced over time.