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  1. diamond tetra - photo by Erik Olson (from the GSAS gallery).
  2. bleeding heart tetra - photo by Erik Olson (from the GSAS gallery).
  3. [FRESH] Flame Tetra (Hyphessobrycon flammeus) experiences
    by oleg-at-Veritas.COM (Oleg Kiselev) (30 Oct 91)
  4. Breeding Tetras
    by oleg-at-Veritas.COM (Oleg Kiselev) (21 Jul 92)
  5. Breeding Tetras
    by ( rosa) (Tue, 21 Jul 1992)
  6. [F][Q] Breeding Congo Tetras
    by (Patrick Bizon) (Tue, 16 May 1995)
  7. Cardinals and Neons
    by "don" <don/> (Wed, 30 Jan 2002)

[FRESH] Flame Tetra (Hyphessobrycon flammeus) experiences

by oleg-at-Veritas.COM (Oleg Kiselev)
Date: 30 Oct 91
Newsgroup: rec.aquaria,alt.aquaria

I am not a Tetra person.  I breed killies.  But I had this 10 gal tank
I bougt really cheap and for some strange reasons the killies I was
raising in this tank kept getting weird fungal infections and dying.  I
decided to take the advice of people with more experience than I have
(particularly Joe de Rosa's suggestions) and let the tank sit around
and "air out" whatever it is that was killing my fish.  A part of this
procedure is to keep throwing "junk" fish and culls into the afflicted
tank until they stop dying.

At the San Francisco Aquarium Society auction I noticed a bag of H.
flammeus donated by the Waterline Aquarium store (Mountain View, CA).
There were 4 breeding-size fish in it so I decided to buy them if the
price did not go too high.  The fish looked scared and almost
completely colourless, but I was going to use them for my evil
experiments with the "killer tank," so I did not care all too much.
Plus they are supposed to not be a very hard tetra, so it could be an
interesting experiment.

The bidding started at $.50 and stopped at my bid of $4.  At the
regular price of $3-4/fish, this was a steal, especially for full grown
specimens (1.5").  I put the fish in the "killer" and by the next day
they coloured in enough to look like the Flame Tetras should.  I tried
to sex them and decided that I definitely had 1 male, 1 female and 2
fish I could quite tell.  I went to the Waterline a few days later and
bought another 2 fish (it's nice to know people at the shops enough to
have them let you catch your own fish), trying to get 1 definite female
and 1 definite male.  By the end of the week one of the tetras died --
I think it was the one I bought at the store.  It appears that these
tetras are easily stressed and do not handle stresses all too well.
The ordeal of being chased through a 90 gal tank with 300-400 other
tetras may have stressed them too much, or I may have succeeded in
catching only the slowest fish of the set I was targeting (I did not
want just any fish out of that tank!)  So far this was the only tetra
death in 3.5 months.

This is a regular 10 gal all-glass tank.  Initially it contained a 
layer of Water Sprite mixws with Salvinia and Duck Weed at the surface
and a large (10"x10"x6") pillow of Java moss.  The bottom of the tank is
covered a thin, patchy layer of boiled peat moss which I have so far changed
twice (by siphoning it off in major water changes).  The tank is filtered
by Tetra's smallest sponge filter, Tetra Billy.  The lighting is provided by
a spare 15 watt wide spectrum Aquarilux fluoresecent bulb in a non-rapid
start fixture, which results in the light pften being left on for days
because I forget to turn it off.  

Lately I added a large pillow of live sphagnum moss at the side of the tank
not covered by Java moss, leaving just about no parts of the bottom
accessible to the adult fish.

Water chemistry (at the moment it is dumped into the tank): 50-120 ppm (the
water quality has been spotty), 3-4KH, about 7.5 pH.  Because the water is
relatively soft the peat acidification takes it down to 6.3-6.4 pH.

Water temperature: it was in high 80's around September.  2 weeks ago it
dipped to 60F for 2-3 days when a sudden cold snap caught us with all 
windows open.  Since then I added a small heater to the tank and closed most
of the windows, so the temperature is around 76F.

Feeding: plentiful!  Primarily live baby brine shrimp, with occasional live
adult brine shrimp and Grindal worms.  Lately I have started supplementin
the diet with an occasional pinch of vitamin enriched OSI Freshwter flake

This tank is sitting on the table right next to my computer stand, so I
take a look at these fish now and then.  When I put the tetras in, the
tank was still inhabited by some left over Cynolebias constancie runts
and a lone Aplocheilus dayi male.

The fish fight peridic territorial battles and are not what I would describe
as "very peaceful" -- they will not bully any non-tetra species and their
own "fights" do not result in any damages, but they are not all too mellow
and plenty of swim room with many territories is important in a small tank.
It appears that in a large tank, with a hundred other tetras, these fish

I had seen these fish spawn twice.  Once it looked like there wasn't
much going on -- the dominant male and one of the females were dancing
around each other, the female missing the male by not guessing the
direction of his movement now and then, looking incredibly silly as she
would stop and try to figure out where he has dissapeared, then
catching up to him.  I did not see any eggs.

Then, one evening, I noticed the eggs in the Java moss -- tiny, shiny
clear spheres -- and the Tetras were busily trying to eat each and
every one of them pausing their feast to spawn again and lay another
few eggs.  I really did not expect to see any fry.

But a week or two later I was shicked to discover a small (1/4") fry
darting in the Java moss, already sporting red anal and caudal fins
(ventrals are clear at that stage).  While looking for it the next day,
I noticed a couple of smaller fry and a tiny translucent sliver of
something that did a rapid dash into the moss.  This was when I posted
my previous article about the Flame Tetras, including a question about
how often they spawn.

I pulled the killies out of that tank (and the Aplocheilus dayi had not
appreciated that at all and died a few weeks later -- I could not quite
match the pH he preferred in another container), so the only predators
left in the tank were the tetras.  And what poor predators they make!

At the moment I can see 3 dozen Flame Tetra fry in that tank, ranging
in size from really small ones that hide in the lower reaches of the
tank, under the Java moss and the Sphagnum, to the easily sexable 4/5"
juveniles.  There are probably a lot more babies deeper in the moss.

I have done only 2-3 water changes in this period of time, with periodic
"topping off" to make up for evaporation.  These water changes are about 50%
at a shot, but I try to slowly drip the water back in to avoid drastic
water chemistry changes -- 5 gal in about 1 hour.


It appears that these fish spawn all the time.  Other tetras, like Neons and
Cardinals, are said to spawn only every 2-3 weeks.  The fry grow quite
rapidly and presence of fry of just about all sizes suggests frequent

Based on my observations, the temperatures do not matter as long as they are
within "normal" bounds (72-86F).

Live foods may be one of the major factors behind the tetras' willingness to 

Low pH seems to be important -- I get more fry as the water gets "older".
Peat moss and possibly Sphagnum moss are responsible for it in this tank.

Creating a near-total bottom cover with fine-leaved plants is important --
the eggs fall through to the peat moss and the adults are not able to eat
them.  It also protects the younger fry from predation.

I can not discount the water softness as a yet another factor in egg
survival and fertility.  I am not quite sure, but it appears that as the
tap water quality had improved (TDS went from over 90 ppm down to 60) the
amount of fry increased.

Light does not seem to harm the eggs (it is recommended that Neons' eggs be
kept in complete dark), but the light levels under the thick layer of
surface plants is not all that high.

The fry most probably eat rotifers and infusoria on the plants' leaves, 
"graduating" to baby brine shrimp when they get larger.

It's pretty easy once you learn what to look for.  Males have much more
intense red colouration,?especially in the ventral and anal fins, with a
very dark black edging on these fins.  Females have a paler red colour and 
the black margin is very narrow and faint.  But the most telling factor 
is the shape of the anal fin: its lower margin is nearly straight in the
males and is somewhat indented (concave) in the females.

Here is the horribly exaggerated ASCII picture:

	\       /		\     ___/
	 \    /			 \  /'  
	  \_/			  \/

It was very easy and did not require anything elaborate -- I set up what I
thought were appropriate conditions for the fish and the did what comes
naturally.  A bit of foresight in setting up the tank had resulted in the
environment where the fry were able to hide untill they got too big to just
get eaten.  I suppose the predation is very heavy, but enough fry survive to
suggest that I had done too good of a job setting the tank up -- I really
have no space to be raising a bunch of tetras to a selling size.  As long as
you feed them well with high quality food and the water is acceptable, 
the fish will spawn.
Oleg Kiselev                                   
VERITAS Software                           ...!{apple|uunet}!veritas!oleg

Breeding Tetras

by oleg-at-Veritas.COM (Oleg Kiselev)
Date: 21 Jul 92 (Howard Rebel) writes:
>late 60's) indicates that tetras in general are very difficult to 
>breed and that most tetras being sold were caught in the wild.

Tetras need specific water conditions and specific set-ups that minimize
egg and fry predation.  Without these factors the breeding of tetras is 

A lot of tetras are still caught in the Amazon delta and imported.  This is
in part because many tetras are sort of like the piscine equivalent of
roaches and breed in huge numbers, in part this is because they are cheaper
to catch in Brazil than to raise in US or Indonesia.  If carefully managed,
the supply of the wild tetras can be sustained and harvested forever, but 
deforestation, polution and over-fishing may destroy theor populations.

>Are tetras still difficult to breed ?

Depends on what tetras you have in mind.  Some are very easy, some are not.

Until this week I had a 10 gal tank with free-spawning Flame Tetras 
(Hyphessobrycon flammeus).  In it I had a large pillow of Java moss, 1/4" of
peat moss on the bottom of the tank instead of gravel, a layer of Salvinia 
at the surface, and a small Tetra sponge filter.  The water was moderately 
soft (30ppm-100ppm depending on the season) and neutral to acid pH (7.0 
down to 5.5 depending on the hardness and the freshness of the peat).
The tetras spawned in the Java moss, ate the eggs and fry they could reach,
but enough fell deep enough into the moss to hatch and grow into something 
not so easy to catch and eat.  

The other tetra tank I have is the Lemon Tetras in the tank in my office.
It's a 10 gal with one AquaClear 150 and one AquaClear 200 filters (now set 
to minimal flows, so they chop up fewer hatchlings).  The decor is a huge
piece of driftwood, some Java moss, a large bare-root clump of Anybias nana.
The water is very soft (17 ppm), slightly acid (6.8 pH) bottled drinking 
stuff.  I have a couple of dozen fry of various sizes in the tank, so I
introduced a "biologocal control" into the tank: a few small Aspidoras

In both of these tanks the tetras spawn(ed) continually and the fry survived
due to a sufficiently dense refuge of Java moss.  The fish were given a
large enough space to swim and interact, so they did not constantly menace
the spawning sites.  One tank was under-filtered and very acidic, the other
is drasticly over-filtered and near neutral pH.  In one tank the fish 
got a lot of live foods, in the other tank the fish mostly get flake food

Try a healthy group of flame or lemon tetras -- in my experience they are 
not difficult.

"... i heard the droning / in the shrine
             of the sea-monkey / palace of the brine ..." -- Pixies.
Oleg Kiselev                                   
VERITAS Software                           ...!{apple|uunet}!veritas!oleg

Breeding Tetras

by ( rosa)
Date: Tue, 21 Jul 1992

In article <1992Jul21.074655.28509-at-Veritas.COM> (Oleg Kiselev) writes:
> (Howard Rebel) writes:
>>late 60's) indicates that tetras in general are very difficult to 
>>breed and that most tetras being sold were caught in the wild.
>A lot of tetras are still caught in the Amazon delta and imported.  This is
>in part because many tetras are sort of like the piscine equivalent of
>roaches and breed in huge numbers, in part this is because they are cheaper
>to catch in Brazil than to raise in US or Indonesia.  If carefully managed,
>the supply of the wild tetras can be sustained and harvested forever, but 
>deforestation, polution and over-fishing may destroy theor populations.
>>Are tetras still difficult to breed ?
>Depends on what tetras you have in mind.  Some are very easy, some are not.

[Oleg describes his set-up for breeding Flame  and Lemon Tetras deleted]

>Try a healthy group of flame or lemon tetras -- in my experience they are 
>not difficult.

There are lots of other tetras that are easy to breed. I started with Black
tetras, and quickly had more fry than I could handle. Glowlights are another
prolific fish, and very easy too. Permanent set-ups like Olegs work best with
fish that breed constantly, like Emperor Tetras, but even Diamond Tetras are a 
good fish to try in such a tank. Pick one of these tetras, get 6-8 and put 
them in a 10-20 gallon tank with some peat (live sphagnum works even better)
feed them well and keep the tank clean. You should see fry within a few weeks.
Of course this assumes initial stock was sexually mature.

Joe DeRosa

[F][Q] Breeding Congo Tetras

by (Patrick Bizon)
Date: Tue, 16 May 1995
Newsgroup: alt.aquaria

> 1 - At what size are these fish considered sexually mature?
      I have breed neon and black tetras but would think congcos are mature
      at about the size you got.

> 2 - What water conditions are needed for breeding?

      Slighty acidic, 6-8 to 7.0 temp should be 80 to 82 dir.

> 3 - What tank conditions (i.e. rocks, plants) are preferred, if any?

      No gravle or U/G filter, use marbles about 2 in thick from the bottom. 
      I also used small clumps of yarn about 1/2 acrossed and about 4 in high 
      stuck in the marbles at the bottom. Filtration needs to be very slow, a 
      small box filter with very little air flow in a ten gl tank works well.

> 4 - What behavioural breeding rituals are exhibited?
      The females will get plump if given live food in small portions many 
      times a day. No more then they can eat in two to three min. Do this about 
      four to five times a day. The males will chase the females and firtilize 
      the eggs as she releases the into the yarn. Then they will fall into the 
      marbles were the fish can't get to them to eat them. After they are 
      finshed (one to two days) remove the fish.

> 5 - What care is recommended when hatching eggs and raising the fry?
      Keep the water clean and do 15 % water changes every few days. The eggs
      hatch in about a week but the fry are hard to see at first. You need to 
      feed them microscopic food eight to ten times a day. To make some, soke
      some lettus in tank water a mason jar works well. After three days get a 
      microscope and look at some of this water. Use an eye dropper and suck up 
      the water next to the lettus. Feed an eye dropper full eight to ten times 
      a day. Squrt it near the bottom .You will need to make a new batch every 
      few days as this will foul in about a week. After a few weeks or when they
      look big enough, start them on flake.

      Good luck and have fun.


Cardinals and Neons

by "don" <don/>
Date: Wed, 30 Jan 2002

Back when I worked in a pet store, the owners wouldn't stock neons or 
cardinals because they said they would lose 50% of the stock 2 days after it 
arrived, and more losses as time wore on.

I convinced them to buy another batch of cardies and let me take care of 
them. I cleaned the &$#& out of the 20g tank they were going in, no central 
filters in the freshwater tanks only ug's, removed the ug plates and put in 
a cycled bio-wheel 160. pH of the tap water there is 7.6, rather hard. The 
cardies came in (50 of 'em in a large bag of water). I tested the water in 
the bag when it got there and it was 6.0!! I dropped an airstone and put a 
coupla drops of amquel in the bag and watched the pH climb to 6.7. So the 
bag was low on oxygen. Too much CO2 from the fish. 

I left the airstone running for another hour, and scooped out a cupfull of 
water and started dripping water from the tank they're going to. After a 
coupla hours the water had been almost completely exchanged, pH was 7.5. 
Close enough. I dumped them in the tank at that point, not netting them for 
fear of damaging them physically. I figured the risk of disease from the bag 
was much lower than the risk of harming them. 

I put a "Not for sale" sign on the tank for 2 days. Lost only one cardie. 
The rest sold out completely over the next week. 

Needless to say, if properly cared for and transferred (unless there are 
other factors as have been mentioned), the fish will do just fine. :-) 

Whew! That was long! LoL 


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