Corydoras pygmaeus spawning questions

[aquanatix]

Always have been a big fan of the pygmaeus,been trying to breed them for quite some time without any success. Tried most methods used to inducing spawning as read online. I've had success with the pandas and sterbais but the pygmaeus just refuse to spawn! My females are literally full and ready yet not much luck. Anyone here succeeded in breeding them? My tank parameters are as follows:

1)16x16x18inch "cube" tank
2)small sponge filter
3)temperature:25deg plus minus
4)about 30% weekly water changes
5)thin layer of river sand on bottom
6)Clumps of spikey moss
7)feeding of frozen bloodworm,sparing amounts of brineshrimp etc...
group of 4 females and 6males
9)water PH 6.5-7

Did anyone spot anything that's amiss? I feel that i'm missing something somewhere? I'm suspecting the much cooler water needed to kickstart the group but can't really put my finger to it,hope someone here could share with me more!

[Quixotic]

Sometimes fishes are like that. If they don't feel like spawning at all, then you will probably have to wait a long while before they get interested, no matter what methods you tried. But once they started, they will just keep going on and on and on...

I don't see much issues with your setup, except that the group that you are using is larger than the reference that I have. I am not sure if that is a factor, but checking Werner Suess' Corydoras book, he uses just a pair or in a ratio of 3 males to 2 females. *shrug*

Perhaps you would like to try just using a pair and see how it goes. Good luck.

[aquanatix]

Thanks for the suggestion Quixotic,will try it out in another set up and see how it goes!
Very frustrating to always see full bellied females and yet no spawn!
Would be a pity if these cories do not spawn,crazy about them!

[Freshman]

How about getting some tall leaves plants for them to deposit eggs?

I saw a photo of C.hastatus setup in other forum. It has hornworts lookalike plants and several ceramic rings on the floor for the newly hatched babies to hide.

My ex C.pygmaeus love to rest on the big nana leaves. They also swim around there during daytimes.

Btw, are the water parameters all OK? ammonia.etc..

[celticfish]

The rain we are having in Singapore should help some now.
Once a week water change may not be sufficient to trigger the "rainy season".
I have read reports about daily water change for a week and more, for stubborn species.
Though I don't think C. pygmaeus is a stubborn one.
If you have an empty tank use it to maintain the water quality for your WC.

[aquanatix]

Hi freshman,tall leaved plants are not very feasible in my case.All i have are fine river sand,having other plants besides moss would mean pots?Not sure how it'd work out other then just dumping them in straight into tank and hope that they'll stand?
Guess i'll just do a few more water changes per week.And yes celticfish,its precisely because of the rain and cooling weather that's making me fustrated! This should be the ideal period to try spawning them!Argh...

[Freshman]

You can attach the plants onto driftwood.

I'm sure they would love to have some resting place in the 'air'

Beware of any death trap - previously a few of them got stuck in my filter inlet gap.

[aquanatix]

Got that once,the poor fish got itself stuck onto my filter inlet and virtually got it's skin ripped off!Not a pretty sigh...And there i was wondering what my shrimps were all crowding around when i picked it out.Wil try out a few more setups freshman,i'll get it right SOMEHOW!

[stormhawk]

My pygmaeus spawned for me like clockwork in the past. I'm not sure what's wrong with your group, but they should spawn pretty soon after a water change. I didn't do much with mine. They were left alone and fed with live tubifex and some tablet food. The males will just pursue the females all over the place.

A little suggestion, maybe you can use some cold water kept in a bottle in the fridge. A little temperature change might trigger them to spawn. Keep a good watch on them though. You could buy a small piece of driftwood with some Anubias attached. It might make them happier. That said, the ones I had spawned in a bare-bottomed tank with some driftwood that had Java Fern and Anubias tied on it.

Here are some old images that I took from the spawning I had in 2003.


The pair flirting


Standard "T" position that Corydoras do prior to spawning.


Female with the egg held in her pelvic fins


Searching for a spot to deposit the egg


Egg deposited on the aquarium glass

I have a picture of one of the fry somewhere, but it's missing from my collection. Oh well, none of them survived back then. Something happened and the whole batch of fry conked out. Subsequent spawnings were fertile, but I kept losing the fry.

The parents died off about a month or two after I moved them to a different tank. They never spawned again after the move. I hope the pictures will encourage you to get successful with your pygmaeus.

[celticfish]

Nice of you to come out of your shell with the report and picture stormhawk!

[aquanatix]

Thanks for the images stormhawk!Your pictures sure made me wanna keep at it! Will try it out and report findings again!Will go look around for a nice piece of driftwood with anubias. Let's hope all works well?

[stormhawk]

Haha Celtic, yes I've been lurking more and posting less. At least I remembered I kept these images somewhere.

Good luck aquanatix. Hopefully yours will spawn soon. I feel like trying some again, but not at the moment. I don't have the extra tank space to devote to breeding them again. My attempt with some Rams failed miserably after the last female conked out, so I'm trying my luck with some other Apistogramma. When I have the time to set up a proper species tank, I'll try out the pygmaeus again, for old times' sake.

As for the driftwood with Anubias, if you're in the west just get them from C328. Occasionally there'll be a spider or some bug that comes with it.. Just remember to rinse it well before placing it into the tank.

[aquanatix]

Haha...good luck with your Apistos! Hope you'll go back to the pygmaeus in time to come.Saw some of the anubias driftwood over at C328,priced pretty reasonably.Spider or bug?Erm...guess i will need to take extra care with it!

[stormhawk]

I had a spider that came with a coconut "house", those half coconut husks with a fern or moss growing on the top. Had to hose it off the fern since it was hiding amongst the leaves. I've seen some sort of wood lice living on the driftwood in one of the plant farms, so it won't surprise me if they have some "stowaways".

That said, something happy happened today. I noticed my C. trilineatus swimming frantically around the tank, with one of them constantly cupping the pelvic fins together in the "basket" formation like you see in the pygmaeus pics earlier. I thought they had started spawning... well guess what.. they did!



The egg is near the top right corner, use the snail at the bottom of the pic as a reference to size. I only found this single egg so far, I figure they are still spawning because the males are still actively chasing the females around. By the way, this egg was deposited right along the path of my canister filter's spraybar output.

[celticfish]

Congratulations stormhawk!!

Good to also hear similar expeience of eggs being deposited in direct flow of the filter.
My sturisomas always seem to pick those spots for egg laying.

[stormhawk]

Thanks celtic.

Now my big problem, that egg went missing a few minutes after I took that shot with my HP's camera. I should have rolled it off with my finger and transferred it to my breeding trap in the tank after I took the shot. High chance one of my tetras or barbs gobbled it up. The trilineatus have not shown any further interest in spawning. They just got a heavy feeding of tubifex. I figure another water change tomorrow might trigger some action.

[aquanatix]

Great news stormhawk! I'm guessing depositing eggs near the outlet provides ample aeration and possibly cooler temperatures? But the recent wet weather is great news actually,my pygmaeus are going crazy! Did observe breeding behaviour but decided to leave it for a few days just to savor the suspense! Will scrutinize the tank for egg deposits later! Wish me luck!

[stormhawk]

Good luck man. If you happen to spot the males "dancing" around the females then spawning is imminent. In the past my pygmaeus males would flirt alot with the females. With the trilineatus, the male basically follows the females everywhere, and then arches himself in front of her, presenting his belly region to her mouth. If she is willing she will nudge his belly region and both will freeze for awhile. It seems that she "inhales" in the male's sperm while she lays an egg or several eggs into her pelvic fin "basket" and the sperms pass through her gills to fertilise them. I kept seeing this action over and over again. Sometimes the female will not lay any eggs, but keep doing this repeatedly, like a dry run.

As stated in one of the cory books, some of them like to deposit their eggs close to the output flow of a power filter. Seems they love the aeration that such currents bring, plus the current basically keeps the egg surface clean of debris.

I hope you'll get some real action soon. Pygmaeus babies are tiny but adorable even in newborn stage. Like mini tadpoles.