Raising cory fry

First off I have to say there are no hard & fast rules, this is just what works for me.

To encourage spawning feed well with, bloodworms, micro worms, black worms, brine shrimp etc, then do several cool water changes over a couple of days dropping the temperature a few degrees.
You can also try lowering the water level around an inch each day over a week & at the end of that week refill with cooler water to simulate the rains which should encourage spawning.
You may have to do this several times to get them going & it won’t work for all species, especially wild caught, but I’ve found it seems to work for most of the commonly available species.

If the eggs are laid on plant leaves then just remove the leaf, if the eggs are on the glass there are several methods of removing them.
You can use a razor blade or credit card to carefully scrape the eggs off or rub a clump of moss gently over the eggs & they will stick to the moss so you can remove them.
I place the eggs in a food safe tub with some tank water & an airstone on a low flow setting & float it in the main tank to keep it warm & do small daily water changes with water from the parent tank.
Some people use a couple of drops of methylene blue to help prevent fungus, I've found thanks to a tip from a cory expert, that Alder cones do a good job too, if you use Methylene blue make sure all is removed before the fry hatch.

The eggs if fertile change colour from white to a creamy brown after about 24 hours, any that stay white or look fungusy should be removed, a turkey baster is ideal for that.
Depending on temperature, I usually have mine around 24C, the eggs should hatch in 3-5 days, once hatched don't feed for 3-4 days while the fry absorb their egg sac, after that you can begin feeding.
Microworms, black worms & baby brine shrimp are all excellent fry food, if you can't get any of those then a food such as HikarI First Bites or catfish pellets very finely crushed will be fine.
I use Oak leaves in my cory tanks & always add some to the fry tubs & tank as the fry can shelter under them & also feed on the insuforia they produce.

Keep the bottom of the tub or tank clean as fry are very susceptible to bacterial infections, I add a thin layer of sand to help & it's quite amazing how quickly you'll see the fry sifting through it to find food. Do daily water changes with water from the parent tank as the fry need feeding several times a day & the water can quickly become fouled.

If you've used a tub to hatch the eggs, once the fry are a little bigger & stronger a 10 gallon, with heater & sponge filter is a good size to move the fry to.
Use water from the parent tank to about 6" in depth, you can gradually increase the depth over the next week or so, again using mostly water from the parent tank & a small amount of new dechlorinated water.
Keep an eye on the water stats as the fry are sensitive to any changes in water quality, if everything remains good & with good food you'll have happy healthy fry.
Hope that's helped answer some questions.

Edit: a clever idea from Mattgirl how to make a hatchery for the eggs.

I built a DIY hatchery for my cory eggs. It is made out of a small "Move over butter" container. I punched tiny holes all around it about 1/2 inch from the top. I also punched 2 holes to attach suction cups.

The suction cups hold the hatchery in the corner of the parent tank and the tiny holes around the top edge keep a constant supply of fresh water running through it. Even though it is getting fresh water I still use my turkey baster to remove some water from it a couple of times a day to make sure the water stays fresh. As I am removing water fresh water runs right back into it.

A couple of videos of corys spawning
Corydoras spawning videos | Corydoras Forum | 455564

 

Thank you CoraDee! Great bookmark!

Ken

 

all this is helpful so thanks.
one question I have I have my cory fry in a 19ltr nano tank ive read that to much water can drown the fry is this true? how full should I have my 19ltr tank?

 

Unless it's a really tall tank then they'll be fine getting to the surface.

 

Coradee, I've had 6 happy False JuliI Corycats (plus 1 DG, 7 Neon Tetra) in my 20-gallon cycled tank (with Annubias, some plastics, caves, air stone), w/Fluval-30 filter for about six months. Parameters are always good. I now see three Cory fry in this tank, to my total astonishment. I've done no special feeding, no drop in water temp, no food for the fry, yet there they are - 3 different ages, perhaps 2 to 4 weeks old. I probably have room in this tank for them to grow up, but it's pushing it. I do about 30% weekly water changes, but I am worried about being gone for a two-week period (in a few months). Coradee, you mentioned fry are susceptible to bacterial diseases. I am thinking of putting some National Geographic Herbal Relief for Bacterial and Fungal Diseases in the tank for a couple of days as a precaution. (I know to take out the carbon filter.) I've used it in the past, once when I had a platy with fin rot; I removed him; he did not survive, still I wanted some type of precaution in the tank for the remaining fish. I would very much appreciate your opinion on this Cory situation! I thought Corys were not "easy to breed". Ha. Maybe not so true. (I think my LFS will take them if you think the tank will be too crowded.)

 

If they're in the main tank & doing well I'd leave them there. I wouldn't add any more of the meds either, it's really only when you're raising a lot of fry in a smaller tank that there's a higher risk of bacterial infections.
By the time you go away they'll be that much bigger & should be fine especially in the large tank, I've left fry for 10 days before & they've been ok.
Good luck with them, hope they continue to do well

 

Caradee, Thank you so much for your comments. I'm happy to hear they should do well, but one more question: aren't False JuliI Corycats difficult to breed? That is what I've heard - special feeding, lowering water temp, etc. and then special feed for the fry. That's why I was so surprised to see these little ones in the tank. Sooooo -- is it quite possible that I may expect more fry in the future? (Note: my Gourami leaves fry alone. )

 

Coradee, I am still curious to know if False JuliI Corycats are usually difficult to breed, Is it possible that water changes may indicate "spring runoff" to them - and time to spawn? Is it likely I will see more fry? (If so, I will be making frequent trips to my LFS as I do not know anyone locally with a fresh water tank who might want to adopt them.) Thank you in advance for taking time to address these issues.

 

Sorry, I must've missed your question.
C.trilineatus are pretty easy to breed but in a community tank you won't get large numbers of survivors so I wouldn't worry about a population explosion.

 

Thank you, Coradee. The problem is the tank size: only 20 gallon, so I really do not have for any more. These three really pushed the limit, in my opinion. And now I may have four rather than three. (It is difficult to count them as they are rarely altogether, they all look the same, and when resting, the little ones "disappear" - all of which I'm sure you know well!) They sure grow fast!!

 

Coradee, how big should baby corys be before I let them in the 150 gallon tank? With 8 glow fish, 7 adult corys, 1 clown loach, 5 guppies, 1 sword tail and about 10 dalmatian mollies. Tank has been established for a year now. Found ~18 baby corys in bottom of my fIlstar filter 2 weeks ago! They are doing great in a nursery in the big tank, growing a little everyday. I have experience with Molly fry (like everyone I guess) but never catfish. Thanks ahead of time for you help. I read the raising Cory fry thread also. I guess my main concern is when to let them in the big tank, so they don't get devoured.

 

I was totally not expecting it but I just found a Peppered Cory fry wandering around the bottom of my tank! Hopefully it'll be okay!

 

Great read what is methylene blue can I get that in Australia?

 

Methylene blue is a very old but effective med for preventing fungus in eggs plus many other aquarium uses.
You should be able to get it in Australia, I would a pharmacy would be the best place to look.

 

So I've had 8 Corydoras Aeneus for less 48 hours now, and I awoke this morning to find eggs scattered through my 75 gallon planted already. My Angels and Rummynose tetras were all huddled into one corner, I freaked at first, until I realised it was just Cory egg feast time.

There were ALOT of eggs, mostly on the glass but also on plant leaves. I managed to fill up my 20 gallon quarantine with my 75's tank water, and only using my fingers, transferred 17 eggs over to it. They are stuck to the glass, beside my sponge filter. It's sitting at around 25-26c ( the parents laid at this temp).I can't believe how sticky and strong the eggs are. I thought I would burst them, just buy lightly sliding them off the glass, but they are so solid.

Anyway, what are my chances of successfully raising these guys ? I'm increasing my school to 15, but it would be cool to have raised te next batch rather than buying another.I have bred a lot of S.A and C.A cichlids, and raised some simple Cichlid species (kribs, firemouths, convicts etc)but never attempted catfish. My L168's are te only cat I've ever planned to breed and raise.

Any tips on hatch rates, growth rates, feeding or anything in particular about raising corydoras would be well taken in at this point. I have zero experience in this area of breeding, so I'm all ears!

Here is a photo of the clutch of eggs being destroyed by my angelfish, even though it was right near a power heads outtake, they were more concerned about eating the eggs. If you look closely in the fist photo, you can see eggs on the other end of the tank aswell, stuck to the glass.




And them now in my 20g





Sorry for the horrific pictures, I was rushing.

DoubleDutch I would love to hear from you if you have the time!

 

Hi! I know very little about Cory breeding, as I've only read about it but I think I read the white eggs are dead and will fungus over and the yellowy eggs can survive.

 

Hi! I know very little about Cory breeding, as I've only read about it but I think I read the white eggs are dead and will fungus over and the yellowy eggs can survive.

Thank you! I think you are correct about the egg coloration, It's the same for all egg layers I believe.


I'm assuming at this point all I can do is wait, hope they are properly fertilised, and don't fungus over? I have separated them an inch or two from each other on the glass, in hopes they don't spread to one another if some do turn to fungus. The sponge filter is bubbling only 2-4 inches away from the eggs.

My biggest concern is how high my water level must be for my sponge filter to work (it's a big sponge filter). I didn't know cory fry needed shallow tanks to get air from the surface easier. The lowest I can have my water level is around 11-12" in order for my sponge filter to be able to work. Is that to deep ? I might need to go and buy a shorter sponge filter.

My next main concern is diet. Is there any readily available foods that are great quality and easy to feed. I don't really feel like getting into hatcheries at this point, but I will I it's a necessity.

If things go well, i'm going to put in some sand from my established tank before they hatch. Just a super, super fine layer along the bottom, aswell as a small piece of established driftwood. I think the well established bacteria would help them, aswell as possibly providing more of a natural food source ?

 

All cory eggs when laid are clearish white and as they mature they turn a more brownish/yellowish color. the ones that have fungus will be very noticeably different from the rest, unless they all fungus. Fungus eggs are sort of hairy looking.
The eggs will hopefully hatch in 3-5 days and then they will look like eyelashes or little ! on the bottom of the tank.
Don't feed them yet as they have to absorb their egg sac in 2-3 days you can start feeding food such as HikarI First Bites, Baby brine shrimp, finely powdered fish flake/ pellet. try not to over feed, as it will pollute the tank- try to feed them small meals multiple times a day.
Do water changes frequently to keep the water fresh and clean, sucking up any debris from the bottom, try not to suck the babies. use a flashlight if needed to see clearly.
Also remember if these do not hatch/ or die after hatching you will have other chances to try again, as your cories will likely with good food and water will breed when you do water changes that are slightly cooler then the tank.
My bronze cories laid 300+ eggs every month I finally didn't remove any and they are lunch for the other fish.

is your sponge filter established or new? If new you might have to watch your readings. Good luck

 

All cory eggs when laid are clearish white and as they mature they turn a more brownish/yellowish color. the ones that have fungus will be very noticeably different from the rest, unless they all fungus. Fungus eggs are sort of hairy looking.
The eggs will hopefully hatch in 3-5 days and then they will look like eyelashes or little ! on the bottom of the tank.
Don't feed them yet as they have to absorb their egg sac in 2-3 days you can start feeding food such as HikarI First Bites, Baby brine shrimp, finely powdered fish flake/ pellet. try not to over feed, as it will pollute the tank- try to feed them small meals multiple times a day.
Do water changes frequently to keep the water fresh and clean, sucking up any debris from the bottom, try not to suck the babies. use a flashlight if needed to see clearly.
Also remember if these do not hatch/ or die after hatching you will have other chances to try again, as your cories will likely with good food and water will breed when you do water changes that are slightly cooler then the tank.
My bronze cories laid 300+ eggs every month I finally didn't remove any and they are lunch for the other fish.

is your sponge filter established or new? If new you might have to watch your readings. Good luck

Awesome info! Thank you so much.

I'll be looking into those foods, and will try to get a variety for them. I will able to do daily, in some cases twice daily water changes, so that's not an issue at all.

They are actually still spawning as we speak, or it's a different female, i'm not sure, but eggs are being laid all over one of my powerheads, while my 4 Angelfish feast n them. I can't believe how easily bred and prolific they are being, considering they have only been in my tank for 2 days. My hopes are not hugely high anyway, so if things don't work out, I won't be overly fussed.

Hopefully the huge supply of cory eggs and added hormones in the water start pushing my Angelfish into spawning mode.

is your sponge filter established or new? If new you might have to watch your readings. Good luck

New!

That's why I'm adding some sand from my established tank, to help kick start the BB. Though, they will be receiving so many, large water changes, i'm not overly worried.

 

Congrats on the eggs, some info here you may find useful
Raising cory fry

 

Congrats on the eggs, some info here you may find useful
Raising cory fry

Thanks! Appreciate the info. That tells me pretty much everything I needed to know.

I'm actually quite excited, and hope atleast a few hatch. I'll keep updating.

 

They have hatched! Well, a few have.

I could not believe the timing though. Right as I was leaving to go back to work after a lunch break, I decided to check on them, and as I looked closely at an egg, it hatched, the first one to hatch aswell, I honestly could not believe it. I'm so glad I decided to check on them again.

Anyway, now I finished work and returned home, it looks as if 11 hatched, and 3 haven't or are not going to, but i'm leaving them for now as they are tan and healthy looking. 3 I removed this morning, as they were infertile (white). I have only seen 3 fry at one time so far, but there is a small, flat piece of driftwood some are possibly under. Obviously they are pretty hard to see aswell, and I don't want to disturb them at this point, atleast not until they are eating in a couple of days.

I also broke my phone at work today! I'll have it fixed tomorrow and get some pictures up hopefully by tomorrow night, if my iPhone camera can even zoom in on them lol.

 

Quick update of the little fellas!

I have counted at one time 9 now, and all appear to be free swimming as of this morning. There is usually 2-3 at a time swimming around the upper region of the tank, but most of the time they are swimming and resting on the bottom.

They are getting fed liquid fry food, along with crushed/dusted HikarI sinking and carnivore wafers4 x daily, with 25-30% waterchanges 2 x daily. I have some fresh cyclops i'm going to try feeding in a few days aswell.

Things seem to be working well so far, and I haven't lost a single fry yet that I know of, I'm quite shocked actually haha.

Here is a couple of pics, my iPhone sucks but at least you can see them.

 

An update, now 7 days old. You can already see the Cory body shape starting to form! I wasn't expecting such quick growth.

 

Ok good because I sucked up what I could! They seem to be doing well so far. I added a tiny bit of sand to the bottom of the food container. I've only had livebearer fry to this point so this is a new adventure! Lol

I have my first group of 3! I was caught by surprise when I saw the eggs, tried to save what I could now they're probably a week old. I have them in breeder net box but plan to move to a 5gal this week! fingers crossed!

 

I have two Bronze Cory babies, about 10 weeks old, fully coloured like miniature versions of the parents and incredibly confident swimmers. They have stayed in the community aquarium from hatching and are both around the size of a Neon Tetra...absolutely awesome little fish and thriving beautifully

 

Unfortunately I found one of my four Cory fry dead it was stuck on the 5 gallon sponge filter idk if I should get another different type of sponge filter I’m really worried that this might happen again or if I should just use a air stone and put some filter media in the tank also if it’s ok to start changing their tank water to water without methylene blue my fry are about 2 weeks old

 

I don’t think I would use a filter that sits on the bottom with fry that like to hang out on the bottom.




This is my fry tank. It’s empty right now because they are in a grow out tank. It’s ten gallons. Barrel sponge filter rated for 40 gallon tank suction cup to side of tank, hooked up to air filter rated for 100 gallon tank. Seems like over kill, but there are times I split the air multiple ways to either submersed or stand alone 1 gallon hatching jars.

 

I have heard about adding MB to keep the eggs from getting fungus on them but if I am understanding it correctly it is usually recommended to remove it before the eggs hatch. I have actually had more eggs hatch without MB than with it. That may not be the case for everyone though.

I don't think I would have it in the water now. I know my cory fry thrive without it. In fact they thrive so well I am overrun with them.

a sponge filter shouldn't have enough suction to pull cory fry in and kill them. I have to think the little guy died or was very weak and then was pulled to the filter.

 

I don’t think I would use a filter that sits on the bottom with fry that like to hang out on the bottom.

View attachment 621596

This is my fry tank. It’s empty right now because they are in a grow out tank. It’s ten gallons. Barrel sponge filter rated for 40 gallon tank suction cup to side of tank, hooked up to air filter rated for 100 gallon tank. Seems like over kill, but there are times I split the air multiple ways to either submersed or stand alone 1 gallon hatching jars.

Thank you for the response I will try finding one similar to yours in the meanwhile is a air stone and filter media in the tank good enough for temporary use

I have heard about adding MB to keep the eggs from getting fungus on them but if I am understanding it correctly it is usually recommended to remove it before the eggs hatch. I have actually had more eggs hatch without MB than with it. That may not be the case for everyone though.

I don't think I would have it in the water now. I know my cory fry thrive without it. In fact they thrive so well I am overrun with them.

a sponge filter shouldn't have enough suction to pull cory fry in and kill them. I have to think the little guy died or was very weak and then was pulled to the filter.

Thank you for the response I was really confused when I didn’t see the fry that went missing until I checked the sponge filter all the four fry were pretty active and fine yesterday

 

Thank you for the response I will try finding one similar to yours in the meanwhile is a air stone and filter media in the tank good enough for temporary use

Hello, if worried about filter killing fry. You could setup a breeding net in fry tank till they are big enough to avoid being sucked up by filter.
I've done this w/cory & bn pleco fry. Hope this helps you!!!!!

 

Thank you for the response I will try finding one similar to yours in the meanwhile is a air stone and filter media in the tank good enough for temporary use

I bought mine off amazon. I’m not sure how you mean in the setup of filter media and an air stone. Do you mean like an old school submersible filter box. Whatever you use short term should be okay. I imagine you are doing water changes every couple of days as well.

As for MB, I use it in a one gallon breeding jar with a small submersible heater and an air stone to prevent eggs from getting fungus. Once the eggs hatch and start to wiggle I use a reusable coffee filter and pour the MB water and eggs through it to separate the wrigglers, then the wrigglers go in a jar filled with water from the fry tank and is submerged in the fry tank.





After they are free swimming in the jar and have been feeding for a week, I release them into the fry tank.

That’s my process for all egg layers. I’m sure others have different methods.

 

Thank you for the response I was really confused when I didn’t see the fry that went missing until I checked the sponge filter all the four fry were pretty active and fine yesterday

I know it is sad but unfortunately sometimes some of the fry just don't make it. The worst time for me was when I lost a little albino cory fry. I have both bronze and albino corys. All of the fry that have hatched for me have been bronze except for the one little guy. It broke my heart when I lost that one when it was about 2 weeks old.

right now I have about 50 3 week old bristle nose pleco fry. I have a sponge filter in their little tank. It has been in there with them ever since they hatched. Most of the little guys (both pleco and cory fry) should be strong enough to avoid being sucked up against a sponge filter.

Hopefully you have now done a water change to get the remaining ones out of the MB water. It really should only be used to protect the eggs. It is no longer needed once they have hatched. I can't say for sure if it will hurt the fry but it is possible.