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As I write this at home, prior to posting it, it is Sunday, 10th October, 2004, and from about 8 pm through to 11:20 pm, my Lemon Tetras have been engaged in a spawning frenzy. It's usually the Pandas that do this after a water change and gravel vac, but the Lemons were obviously feeling frisky too, and so, cue three and a half hours of mad frantic dashing about the aquarium.

Among the observations to make are these:

[1] My 'alpha male' Lemon Tetras, which usually have a fair amount of black pigment on their fins to start with, become very dark-bodied when excited. And, the tail fins shimmer with this incredible gunmetal blue shade. The yellow colour of the body darkens considerably, as though someone has clothed them all of a sudden in very fine sheer black stocking silk with a tiny mesh. Close up, the darkness of the males seems to come from within - Lemon Tetras have a certain translucency of body naturally, and so the main colouration radiates through the somewhat translucent outer integument layers. It is almost as if these fishes have chromatophores deep in the body, including melanophores that grow in size when the fish is excited.

[2] Again, the dichotomy I've remarked upon before with respect to orientation in the water manifested itself. Two males competing for the females "joust" with a head-up attitude making glancing passes at each other in between frantic chasing of the females. When a male finds himself in the presence of a female, and competing males are busy with each other elsewhere, the male adopts a head-down posture and quivers his body as an invitation to the female to spawn. Male "jousting" is accompanied by stiffly erect dorsal and anal fins, while the fins of a courting male displaying to a female will be seen, on close examination, to be 'flicked' into an erect posture briefly, then relaxed somewhat. This is, presumably, one of the signals that a ripe female looks for in order to 'get into the mood' as it were. Among my Lemons, males seem to enjoy more success actually engaging in egg fertilisation with a female if they expend some effort in this courtship fin-flickering and body quivering beforehand. The lesson here is: don't skimp on the foreplay, or the lady will look elsewhere!

[3] If the female accepts the invitation, the next stop is usually a dive into the Java Moss (I have a LOT of this in my aquarium), whereby the male and female press against each other side by side, sometimes almost completely buried in the Java Moss. The moment of egg release and fertilisation is quite explosive - the two fishes suddenly jolt apart from each other, almost as if someone has detonated a small explosive charge between them!

[4] Avid egg hunting is the next step. For those who wonder how on earth these fishes manage to reproduce in the wild if they eat their own eggs, the explanation is as follows. Lemon Tetras, and many other popular aquarium Characins, are 'gang spawners' in the wild. Several thousand pairs (or even trios - a female will happily allow two males to fertilise her eggs at once) will be spawning simultaneously in the wild. This has the effect of blanketing the chosen spawning ground with a 'carpet bombing' of eggs. Needless to say, any egg predators will be full to burping before they've made even a small dent in the numbers, because a mature female Lemon Tetra can produce up to 400 eggs, and if you have 10,000 spawning pairs in a small area, that's 4 million eggs in one go. And in a spawning season, those pairs will be spawing repeatedly over a 3 month period, perhaps once every 3 days. The trouble is, this means that any one pair faces a LOT of competition for resources for its fry once its eggs hatch. So, what does a pair do? Eliminates some of the competition and eats some of the eggs of rival pairs. Trouble is, this same instinct kicks in when spawning in the aquarium, when only one pair is present. And anyone who hasn't seen Lemon Tetras spawn before will be surprised just HOW avidly they track down any possible competing spawn to eat! So, if raising a nice large batch of Lemon Tetra babies is the aquarist's chosen mission, an egg trap of some kind is a must. Even then, the Lemons will still devour some of their own eggs - they're a lot quicker than you are!

[5] If Java Moss is not present (and I'd recommend it as a spawning medium for all manner of fishes if it can be obtained), then plants such as Cabomba, or in my aquarium, Hornwort, will be chosen. If Hornwort is introduced into the aquarium as a 'nitrate hoover' to help enhance fry survival, remember it is extremely brittle, and any stems pressed into service by the parents will be very soon the worse for wear!

[6] Telling male and female Lemons apart requires some fairly close observation. The principal characteristic is the width of the black band in the anal fin. Females have a thin black line, in some cases almost as if drawn with a fine eyeliner pencil. Males have a much thicker band, in top-quality 'alpha males', this will be a third of the depth of the entire anal fin and very noticeably thicker. However, trying to spot this characteristic in a dealer aquarium full of juveniles is probably a waste of time. Far better to obtain a decent sized batch of fish and grow them through to maturity. Once mature, however, these characteristics will become very noticeable once you know what to look for.

[7] If you want the best from your Lemons, I'd recommend interspersed feedings of live foods and colour enhancing flake. Lemons in a bare dealer aquarium look insipid and pale, and let's face it, in those surroundings, wouldn't you? Lemons come into their own when they have plants to swim among, nooks and crannies to explore (bogwood arches with Java Moss growing on them, like the one in my aquarium, will be very much appreciated!) and decent levels of TLC. Hardy they may be, but these are fishes that visibly reward TLC by colouring up to an astonishing extent. Carpet bomb them with Daphnia, Brine Shrimp and Bloodworm for six weeks, interspersed with a colour flake, and they'll end up a nice solid yellow at the end of this. Mature females are actually a better shade of yellow than the males, because they don't darken anywhere near as much when excited, while males darken very noticeably. Plus, males have taller dorsal fins, though this is not quite as reliable a characteristic as the anal fin band width. My alpha males have dorsals that are almost as flamboyant as those of Black Phantoms, though this is exceptional. Even so, if you watch your Lemons for long periods of time, these features will start to pop out before your eyes.

[8] Bear in mind that even in a community aquarium, while Lemons do shoal, the males also engage in 'part time territoriality', although not to the extremes of my Beckford's Pencil Fish that I've written about in another thread. Owners of Silver Tip Tetras will recognise this phenomenon: males adopt a 'landmark', usually a tall plant thicket or some other prominent feature of the décor, as a display station, and when other males appear, dash out to issue challenges to the 'intruder'. "Jousting" behaviour frequently follows this, though in the case of Lemons, this is more ritualised than serious combat. It looks as if they're attacking each other to the untrained eye, but if you watch closely, they always 'pull their punches' at the very last moment. They are a boisterous and perky species, however, and some docile slow-moving fishes might be intimidated by their antics even though the Lemons confine their attentions to their own species. I suspect this is a phenomenon common to several Hyphessobrycon species, along with Black and Red Phantoms if they are observed closely - likely candidates for 'part time territoriality' displays will include Rosies, Bleeding Hearts, Serpaes and Flame Tets. Strange how no-one in any of the books has noticed this, with the sole exception of a very old book by J.M. Lodewijks dating from 1963, who describes this behaviour in relation to Silver Tip Tetras. I've also mentioned that my Beckford's Pencil Fish do this (documented more extensively in their own thread), but this species is a special case. The rule seems to be that if a Tetra species has high-contrast markings of some sort in the dorsal and anal fins, then these are for display purposes of the kind just described. Tetras with clear fins such as Rummy-Noses and Cardinals tend not to engage in this behaviour. Another species that is worth looking out for that has the right kind of fin markings is the Feather Fin Tetras, (Hemigrammus unilineatus). If anyone obtains this species, keep an eye on them and see if they engage in this kind of behaviour too.

And with this little discourse on spawning Lemons and related issues, I shall bid you all happy fishkeeping!



Panda Catfish fan and keeper/breeder since Christmas 2002

Hmmm... Thanks for the observations, maybe they will help me to induce my lemon tetras to spawn. So far, they seem rather prudish, but hopefully they'll change their ways if I help them along...

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And when he gets to Heaven, to Saint Peter he will tell: "One more Marine reporting, Sir! I've served my time in Hell."

Morning sunshine is a definite stimulus to Lemon Tetra spawning. Something the textbooks have got right!

If they're well fed and well conditioned, watch for them chasing each other like the Keystone Kops at double speed. Then you can sit back and watch the spawning mayhem that should follow

Panda Catfish fan and keeper/breeder since Christmas 2002

Woo-hoo!] My lemon tetras were spawning this morning! I haven't even done any conditioning, I just fed them tons of freeze-dried brine shrimp last night. From the time I woke up to about 10:00, they were doing their funky spawning stuff! Of course, the eggs were all eaten, but that doesn't matter to me.

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And when he gets to Heaven, to Saint Peter he will tell: "One more Marine reporting, Sir! I've served my time in Hell."

CONGRATS ON THE SPAWNING
I have tried it with black widow tetra's
and they have began to colour more and me more active dashing through the plants.
hope they spawn soon.

I've never been very lucky with lemons, but my cardinals *apparently* spawned once, as I now have 4 uncalled for fry happily swimming with the adults.

I've never been very lucky with lemons, but my cardinals *apparently* spawned once, as I now have 4 uncalled for fry happily swimming with the adults.

Your lucky that your cardinals even spawned. But to have fry awsome d00d post some pics can i buy one??? lol

http://img.photobucket.com/albums/v398/Kleevage/sdffj.jpg

The ones on the left are the fry--it's been about four months since I found them in the tank.

Last edited by Cup_of_Lifenoodles at 27-Nov-2004 21:35

The spawning decription of the school sounds like when I had my school of fourteen neons. Every Saturday around 11 a.m. they would spawn. My pair of congos spawning starts with the male chasing the female and after my gouramis and rainbows get to eat the eggs. I plan to breed them soon. In my current school of 10 glowlights (6m/4f)(The reason for more males is I got four for a great deal) I will come back later in the day and the males will be dark from fighting with each other and spawning. The females are normally thinner. They spawn about 4 times a week. I will try for fry soon.

Mr, with Glowlights there are several things to be aware of.

[1] Male and female "barrel roll" when spawning.

[2] Fry are very sensitive to carbonate hardness. You have to keep the carbonate hardness of your water very low for the first 14 days or so while rearing the fry, and gradually acclimatise them to increasing carbonate hardness levels, or they die off. One of the reasons they are still a challenge even to the experienced breeder.

I posted a big article on this some time ago, but that was before the 'Year Zero' archiving

Panda Catfish fan and keeper/breeder since Christmas 2002