Green neon tetras for large tank question
I am getting to stock my 120 gallon planted tank. It's been set up for over a
year but so far only has shrimp and Otocinclus. The tank is heavily planted with
plenty of stems and hairgrass, filtered by 2 Eheim 2217 (cleaned monthly) and
receives a weekly water change (30-50%).
<I'd like to use the change water on my house plants>
The main fish will be a school of green neon tetras (Paracheirodon simulans).
Tank mates will be 20 Corydoras similis, 4 Otocinclus, 75 Amano shrimp, and
probably what will end up being 100 or more tangerine tiger shrimp (after
*How many tetras can I get while still keeping the bioload reasonable?* I'm not
concerned with nitrates and phosphates (as it is I have to add some daily for
the plants), but rather other dissolved organic compounds. I've
found minimizing these to be essential for planted tank health. I'd love to have
a large number to see the social interactions at their best.
<Fifty individuals wouldn't be too many, and would make for a nice school here>
Also I run the tank at 74 degrees - is this too cold for them?
<Mmm; yes; as well as the other life listed... I'd raise this to 77-78 F. for
Many fish database sites seem to list a wide temperature range for this species.
<Welcome. Bob Fenner>
Green neon tetras for large tank question /Neale
<<No real disagreements with BobF., but would remind you that this species is
very Cardinal Tetra-like in requirements; as Bob suggests, middling to warmish
conditions preferable to cooler low-end tropical (i.e., the
opposite to true Neon Tetras). Avoid strong currents, but ensure a good oxygen
level by under-stocking the tank and providing steady but gentle circulation.
Softer water also essential here; not necessarily mineral-free, but lowish,
maybe 2-5 degrees dH, certainly no more than 10 degrees dH. Keep the pH between
6 and 7.5 depending on your ability to maintain stable water chemistry.
Specifically, if you're using carbon dioxide fertilisation, for example, link
this to pH, and perhaps use a commercial Discus buffer to ensure stable
conditions. Green Neons (Paracheirodon simulans) have a poor survival rate in
busy community tanks, so choose tankmates accordingly. Small foods, fed in
frequent but rather small amounts rather than one feed per day probably best.
Bob is spot on in
suggesting a big school is best here -- Paracheirodon simulans does not do well
in the usual 6-10 specimen schools people often buy. Cheers, Neale.>>
Re: Green neon tetras for large tank question 5/29/17
Thanks for the information and welcome! What an honor to get information from
the man himself, Bob Fenner.
<Hee heeee. Just a petfish kind of guy Andrew>
I look forward to interacting more with your site in the future. I only
discovered it recently but quickly found
it to be a wealth of knowledge.
Wishing the crew a happy Memorial Day holiday,
<And you, BobF>
Was Re: stagnant water
[Re: a pack of marauding false tetra], stkg./sel.-comp.
Sorry. The false neon tetra or green tetra, Paracheirodon
simulans. Contrary to what I've read, they are not the
placid little demure fish they are described as.
<Indeed? Usually very shy, quiet fish.>
Yes, they are timid, in a way. But they also have an attitude. In a
group, they are usually jockeying for position. It's not like #2
gets that position and accepts it, he's always testing #1. And #3
likewise, with both #2 and #1 as well, just in case. They aren't
*always* doing this and they don't tear each other up, so it's
not as if they are stressed or have too few neighbours (nine in the
group, but they tend to split into subgroups of five and four.) I
don't think they are insecure because they have a large piece of
driftwood in the middle of the tank and lots of plants. When they get
scared they can hide behind the driftwood in a flash. And they
don't bother anyone else but you can tell by their behavior that
they are related to the piranha. And they know it.
<How many do you have? All tetras can become nasty if you don't
keep enough. Six is the minimum number, but really, it may need 10, 12
or 20 specimens before a given species behaves properly. In the wild
they live in schools of hundreds, so we can't really be surprised
when they behave badly if kept in small groups.>
One thing they do is, in dim light they like to hover with tails back
to something solid and heads facing outwards at about a ten degree down
angle watching, watching .. Then all you see is a dark stripe with two
glowing eyes (the iridescent patch runs right through the tops of their
eyes and the eyes bulge out a little, so all you see is glowing eyes.)
From the front it looks very diabolical. If they see a piece of
food they dash out, then dash back. They don't swim calmly along,
they do everything like a cat pouncing on a mouse.
When they eat, they are not polite. Not exactly a feeding frenzy but
definitely not polite.
<Normal tetra behaviour. The idea schooling fish are
"nice" is totally wrong. Remember, the biggest threat to any
animal comes from its own species. Your own species wants all the same
things you do: food, space, nests, mates. At least a predator is only
an occasional threat and one you can stay away from. Your own kind will
in your face a lot of the time, and if you need to school together for
defence, then you're stuck with hundreds of competitors right up
close. So, schooling fish are actually very, very tense, wound-up
animals constantly trying to asset their position in the pecking order.
A territorial fish like a cichlid only needs to be aggressive during
the breeding season, which in the wild may well be a few weeks or
months of the year. But a schooling fish is totally tanked up with
stress hormones all the time, 24 hours a day, 365 days a year. In a big
school, the aggression is spread out a bit, and the dominant fish
can't bully all the others. But in a school group, the dominant
fish or fishes can bully the weaker ones more often, and things like
fin-nipping become more common. It's not unheard of for people to
buy 6 Danios or barbs, and then end up with just one or two of
This is not what you normally read about the tiny little false neon
It would be interesting, if someone at WetWeb has time (ha ha) to set
up a database back end, for the readers to fill in with observations of
fish behavior. It could be done with a php form.
<It's a good idea, but not altogether practical, both in terms
of what we're skilful enough to do, and also in trying to keep all
reports comparable with one another. If someone with an Angelfish says
they found it aggressive, is that because the species is simply
aggressive, or because the fish was a male being territorial towards
another male, or a large specimen than simply ate small Neons as it
would do, or if the tank was too small, or whatever. Nonetheless, you
will find pages on behaviour and compatibility on WWM, and these
include questions and observations passed on my site readers, e.g.:
Tank and water information, how many in the group, what the neighbors
are, etc then a paragraph or two on how the particular fish behaves.
There is a ton of information on the Internet but it seems to be mostly
the same thing repeated 400 times. The information is wide but not
deep, so to speak :)
There's not much beyond "Schooling fish, likes to be in a
group of six or more, prefers soft water ..." That
doesn't really tell you how the fish behaves. The feeling of a tank
changes a lot according to who lives there.
And you guys don't have all day to answer "can you put a frog
in with an Arowana ?" questions. Something where people could
click on a name they are interested in and read other people's
experiences might be a help.
<A while back I wrote an application called "Can I Keep
It" that tried to show people how to choose compatible fish by
removing options when given fish species were chosen.
It was a hassle to make, but it'd be great if there was a website
that did something along these lines.>
Anyway, just an idea ...
thank you !