Nematobrycon Palmeri Tetra Information

[Akasha72]

Hello,
 
I have 9 of these tetra's (4 females and 5 males) and I recently somehow ended up with a baby - I found what looked to be cory eggs on a leaf, added the leaf to a seperate tank and waited for cory fry but what I got was a palmeri tetra fry!
 
The baby has been on it's own in this tank now for around 3 months. It's currently around 1cm in length. Yesterday I harvested yet more eggs from my main tank and these again look to be cory eggs but until they hatch I'm not banking on it. The eggs are currently in a plastic pot in the fry tank so the baby can't get to them but if they are tetra eggs they should be hatching either today or tomorrow (24-36 hours according to seriously fish) If they are indeed cory eggs then I'm possibly looking at around 3 days for hatching.
 
This all leaves me with a serious dilema. What ever hatches will be small enough to be food for the current baby tetra but the baby tetra is small enough to be angelfish food if I move it to the main tank. There is also another problem ... the baby is starting to get colour now and it's eye's are looking bluer every day. So far it's not showing signs of the extentions on the tail or fins and so sexing it by eye colour alone isn't enough for me.
If it is male I'll have to re-home it. With 5 males already bickering over territory adding another will only add to the bickering. If it's female it can be added to the number with no issues.
 
So my question is, has anyone any experience of breeding these tetra's and can anyone advise me at what stage I can accurately sex this fish?
 
I need to make space for any new editions that come from these eggs and I'm dithering over what to do. Knowing the sex of the baby will help me decide on the best plan. I do have another 30 litre tank that is seperated by a siliconed in glass partition. If I'm keeping the current baby I'll have to bring that tank in from the shed, clean it and set it up and add the baby to one side and the eggs to the other. If we think the baby is male it can go the lfs tomorrow and I've no need to mess about changing tanks!!
 
Any help greatly received. Thanks

 

[eaglesaquarium]

Sexing young fish can be a fool's errand.  Most of the time males appear to be females for quite a while (except to the true 'expert eye') until they reach sexual maturity, or very close.  
 
 
If I was in the situation you are in (which I am a bit envious of btw...) I'd go the divided tank route, and add live plants and a bubbler to the side with the eggs and let the one you've currently got grow out a bit more before making a decision.  
 
As for the males bickering and adding another - I've not kept emperor tetras, but I have kept a lot of livebearers - generally, more males are better for spreading out the aggression, rather than less.  Having an odd number is good, as there will always be a 'free male' to join in any fight to break things up a bit as the males engaged will need to keep an eye on the other males.    Males WITH females though is a different equation, but as long as the females aren't being harassed by the males, then I'd say that you might be ok adding the 'male' baby tetra in the end.  At the same time, it might be worthwhile to go to the LFS and set up the arrangement with them for future drop-offs as well, as this egg laying thing may be a regular occurance - or maybe its just a seasonal thing for them.
 
With my panda cories, they went through a bevy of spawns for about a solid year, then they stopped - or more exactly, they were probably just less successful in their egg hiding, etc.  (I never did a thing to try to save them, but let them take their chances.  I ended up with 6 living to adulthood.)
 
 
 
Best wishes Akasha... seems like a good problem to have.

 

[Akasha72]

thanks Eagles. Your reply makes perfect sense. I very much doubt that these eggs are tetra eggs as they were on the glass. The cories seem to be the perfect candidates but as they were layed during the night I can't be certain. I still have no idea how I ended up with this baby tetra ... I had 4 eggs on a leaf that looked like cory eggs and what I got was a tetra! It's very odd.
 
If I can keep this baby I'd really like to. If he/she was one of several it would make sense to pass them on the lfs but giving them one fish seems a waste of both our time. 
 
The odd number of males makes sense. When the bickering starts there is usually 2 tearing up each others fins and then a 3rd will come in and appear to break it up. There is one male palmeri that seems to be 'the boss'. He seems to be the main one with the breeding rights to the females. I can tell him apart as he's got the most elaborate tail and is the brightest in colour - seriously fish seems to back up that theory too.
 
So, for now I'll keep an eye on the pot containing the eggs and wait to see if anything hatches. Setting up the other tank is easy enough, it's only an 18" clearseal tank that I divided up with a pane off glass out of an old photo frame. It'll mean the baby has less room to swim in which feels a bit cruel but I can't have it snacking on newly hatched 'whatever'!
 
I've only had chance to remove suspected cory eggs twice recently. For some reason they seem to spawn during the night and when I get up I can see the remnants but they've been eaten. My panda's though have added to their number all by themselves. I had 4 to begin with but I've got 6 now. I keep hoping my melini's and now my new smudge spot cories will do the same but nothing currently. I'm failing in all attempts to add to their number via the lfs'. Melini and smudge spot seem to be rare around these parts

 

[Byron]

I had a group of Nematobrycon palmeri and N. lacortei together in my 90g for a while.  The aggressive nature of the male N.lacortei to every other fish in the tank (and I moved these fish through four different tanks over several months trying to resolve this but with no luck) eventually caused me to give them a new home, and the person was willing to take both species together (and knew the reason) so they all left the tank.  A few weeks later, fry appeared, and in the end I had 12 N. palmeri fry that managed to escape initial predation and grew to maturity.  I didn't pay attention to timing as this was just a natural occurrence and I was not specifically trying to raise them.
 
Sex in many fish like the characins will be largely determined by the water parameters.  I believe I ended up with mostly females in the group of twelve fry.  They succumbed to a serious protozoan issue some time later and I lost the lot.
 
I never did find eggs, just the 12 fry appeared.  This species like most characins is an egg scatterer, so some eggs may land in a "protected" spot and escape being eaten.  In established tanks there may often be sufficient microscoic food for fry to survive, and the adult fish generally don't seem too interested in them once they are out and about.  I presently have a dozen Black Ruby Barb fry that just appeared, or were rescued from the canister filter during cleanings.
 
Byron.

 

[Akasha72]

Hello Byron, I'd remembered you'd had some of these fish and so I was hoping you'd come along. A shame your not able to give me a timescale on sex determination though. 
 
Can I ask you - did you get to see the eggs? Are you able to give me an idea of egg size? It might help me determine what these new eggs are. They seem far too big to be tetra eggs and the fact they were on the front glass doesn't fit with a fish that is a scatterer by nature.
 
I checked on the eggs about an hour ago and they are still intact and the 24 to 36 hour timescale is up so I'm back to suspecting cory. In general cory eggs are 3 to 4 days to hatching

 

[Byron]

Hello Byron, I'd remembered you'd had some of these fish and so I was hoping you'd come along. A shame your not able to give me a timescale on sex determination though. 
 
Can I ask you - did you get to see the eggs? Are you able to give me an idea of egg size? It might help me determine what these new eggs are. They seem far too big to be tetra eggs and the fact they were on the front glass doesn't fit with a fish that is a scatterer by nature.
 
I checked on the eggs about an hour ago and they are still intact and the 24 to 36 hour timescale is up so I'm back to suspecting cory. In general cory eggs are 3 to 4 days to hatching

 
Characin eggs are much smaller than cory eggs.  I have never found characin eggs, but I have observed the egg scattering during spawning, and the eggs are almost invisible to me.  Usually the fish gobble them up within seconds, but if one or more should happen to fall somewhere and not be found, they will obviously hatch.  The fry actually have a better chance of surviving than the eggs, as the fry can at least move and hide.

 

[Akasha72]

I have seen the females darting into the plants with the male following and I thought it was them spawning ... it's just this leaf with four eggs on it that has had me doubting myself. The only explaination is that the cories deposited some eggs and the tetra's somehow scattered a day later and one lone egg landed on this leaf with the cory egg. It's the only explaination of how this baby tetra came to be. 
 
The other option is that it got onto the sponge filter that was in the main tank and got moved with the leaf.
 
Thank you. I now know for sure that the eggs I collected yesterday are cory. They are larger than cichlid eggs so they have to be cory

 

[Akasha72]

a decision on the baby's fate was made this morning and now I have an empty tank .... well, an empty tank with a pot containing some eggs if you want me to be accurate!
 
I spent a few minutes observing the baby this morning and decided I could definitely see the very beginnings of his forked trident tail appearing. His eyes were a very definite blue. So, a decision had to be made. The cory eggs are definitely viable as one check on them too this morning found them to be much darker in colour ... all good signs that they are nearing hatching. I knew my baby tetra was large enough to eat newly hatched cories but small enough to be angelfish food if moved to my main tank. 
I'm freshly home from my lfs ... they took him in gratefully - also agreeing on him being a boy. Hopefully they can find him a really good home. I feel a little sad. As much as I enjoy raising baby fish, giving them away is hard