Help! My cories spawned! What do I do??

[EllRog]

The reason egg is so good is that you know the fry are eating. Any live food as first food, like green water is very hard to determine the quality and quantity of what is the water unless you have a microscope on hand.I have looked at green water through a microscope and the conclusion was it is inconsistent at best. Sometimes when you are trying to be natural you have to know when to change direction for the benifit of the fish

Egg yolk contains fats and cholesterol which can damage a fish, it will almost certainly cause swim bladder problems if used exclusively for feeding and can lead to underdeveloped organs. The fish cannot properly digest it's proteins. Infusoria is the best food for fry for the first 1-2 weeks as they can hunt it around the tank with ease providing the water level is low enough for the fry to easily find it, then moving on to foods such as microworms and baby brine shrimp onwards. The fry will instinctively eat what they find with no problem, managing growth is more down to the regular water changes, diluting the growth hormones that the larger fry produce to stunt the growth of smaller fry.

 

[AdoraBelle Dearheart]

Re: water changes with fry

Use a white clean bucket. Any fry siphoned up you can simply net out and place back into the breeding container.
View attachment 119473

To vacuum, use a pipette or small airline hose siphon to clean the debris very carefully around the fry
View attachment 119474

Brilliant, thank you! I have pipettes, have ordered a turkey baster too, and I have white and light yellow buckets for tank maintenance, got those when I first got guppy fry, great for spotting them and shrimplets after water changes too!

The tiny fry in your pics are too adorable!

 

[AdoraBelle Dearheart]

We will start with the tank, your tank has a base I think of 15"x15". Traditionally breeding tanks are made long, They are Twice as long as they are high and deep ( eg 24"x12"x12" ) The reason for this is to give the fish room to run. I would never put Corydoras into something smaller than this tank 15 gallons. The shape is important. You have managed to get these guys to spawn, great and we can work with what you have got. Because of the shape and the fact that everybody is on top of each other, the parents have to come out. The baby guppies can stay there they are fine.
I would normally move gavel away from one end or the front of the tank by about 3 inches this gives a section of bare bottom. Important for cleaning and observation. Any food you put into the tank is a suspension it will fall to the base of the tank and will end up at the lowest point, the bare base of the tank. The rest of the base doesn't need to be disturbed, just syphon from the bare base you will see material draft down as you syphon. Only do your normal water changes, make sure you rinse the sponge filters, don't have the filters running to hard.
Feeding egg yoke has been described elsewhere. But use some cotton an old singlet or any cotton you have experiment with different material. The idea is that for new fry the particle size of the egg yoke should be so small you can't see it with the naked eye. The suspension in the tank should look like milk. It only takes a tiny bit of egg to achieve this. That suspension will dissipate into the tank the young fish will pick up those tiny particles. I only ever feed twice a day. Morning and night.
I have said it is possible to leave the parents in the tank. I have done this with a tank 48"x18"x18'' The tank was heavily planted at one end. Once the fish stopped spawning you feed them. The next morning they spawn again and you feed them once the fry hatch they migrate into the gravel bed where they are largely safe, feed egg yoke which drifts to all parts of the tank the fry get food. I have explained why egg yoke feed this way is so good, remember this is first food, I would feed this for one to two weeks depending on the setup and number of fish. Ask more questions if you like or don't understand what I have written.

Yeah, I didn't plan to breed the cories in this tank, it's a temporary tank I got to use as a quarantine tank, and as a grow out tank for guppy fry. The cories are to go in a 57 gallon, but they spawned in this tank before I moved them, lol. I wouldn't keep them in this size tank permanently, bronzes get too big to live in a smaller tank long term.

My other tanks are heavily planted, but since this one was only meant to be used as a quarantine and grow out, heavy planting isn't great for catching fish or quarantining, and the tank light isn't really good enough for plants to flourish.

I think if a breeding tank was designed, the right shape and size etc, that raising some fish with the parents would be fine, and perhaps even preferable. Not sure it would work with cories though, as @mbsqw1d has experienced, cories aren't voracious predators, but they're naturally dopey and scavengers, I could see them eating fry without even noticing what they're eating! I would imagine a lot of fry would get eaten, even in a heavily planted tank with the adults present, but the odd fry surviving.

I'm not opposed to trying some egg yolk, a lot of people do use it. I don't think I'd want to feed it exclusively for the first two weeks though, when the first weeks of development are so crucial for any creature. Would egg yolk provide all of the essential nutrition? Like when feeding adults, I prefer a variety, and would want to feed some live food too. First Bites provide a variety of nutrients, Liquifry also provides a dense liquid food for tiny fry, and I'll be culturing microworms too, which I've seen recommended for cory fry. Also the micro organisms produced by almond leaves, alder cones and moss.

I wouldn't recommend gravel with cories though, adults or fry. Their barbels are too easily damaged, gravel harbours too much dirt and bacteria, and doesn't allow them to practice their natural feeding behaviours. Sand is always preferable for corydoras.

 

[mbsqw1d]

I've been sat watching my lot spawn all morning, so c.palaetus lay approx 2-4 eggs at a time, and theres around 15-20 minutes in-between them erm.. giving one another special hugs.. so far theres been around a dozen eggs and ive managed to grab 2. The rest have been eaten. I guess I could feed them, although I already have this morning. But then would that stop them spawning? In my setup, I can't see how theyd become fry, let alone grow to become adults, without any intervention. My heavily planted 52 gallon isnt big enough or heavily planted enough. And, this is without any other species of fish living in there with them.

 

[itiwhetu]

Egg yolk contains fats and cholesterol which can damage a fish, it will almost certainly cause swim bladder problems if used exclusively for feeding and can lead to underdeveloped organs. The fish cannot properly digest it's proteins. Infusoria is the best food for fry for the first 1-2 weeks as they can hunt it around the tank with ease providing the water level is low enough for the fry to easily find it, then moving on to foods such as microworms and baby brine shrimp onwards. The fry will instinctively eat what they find with no problem, managing growth is more down to the regular water changes, diluting the growth hormones that the larger fry produce to stunt the growth of smaller fry.

Just wondering where the information about fats and cholesterol damaging fish came from. I would like to read the article and also the one about swim bladder problems and underdeveloped orgins. Could you please post the references

 

[EllRog]

Just wondering where the information about fats and cholesterol damaging fish came from. I would like to read the article and also the one about swim bladder problems and underdeveloped orgins. Could you please post the references

Is it worth it or will you just argue that too? Have a Google, I won't engage further as you haven't listened to others and force your opinion as fact. Nothing personal, just not going to debate with you

 

[itiwhetu]

Is it worth it or will you just argue that too? Have a Google, I won't engage further as you haven't listened to others and force your opinion as fact. Nothing personal, just not going to debate with you

I take it from that your statement about egg yoke is your own personal opinion, which is great we are all allowed those.

 

[EllRog]

I take it from that your statement about egg yoke is your own personal opinion, which is great we are all allowed those.

You can believe what you want to believe as theres clearly no changing your mind. It's clear you haven't researched it yourself, if you believe it to just be my opinion, which is worrying as you're advising others to use it.. anyway, I won't be drawn in further, have a great day

 

[FishGuest5123]

Re: water changes with fry

Use a white clean bucket. Any fry siphoned up you can simply net out and place back into the breeding container.
View attachment 119473

To vacuum, use a pipette or small airline hose siphon to clean the debris very carefully around the fry
View attachment 119474

Thanks for the info. I did most of that with goldies too. I think I’ll have to move them to a breeding tank to get any eggs.

 

[FishGuest5123]

I take it from that your statement about egg yoke is your own personal opinion, which is great we are all allowed those.

Nope. I’ve read several places that egg is bad for fry.

 

[AdoraBelle Dearheart]

Um, I wasn't planning to get any fish when I went to LFS today, I swear. I went to take fish in there, and took 35 young platies and mollies.

But there was a single pygmy cory there, in a tank on his own. I asked if they'd be getting more in soon, and he said they weren't available on his last order, but he'll get more when he can, so I decided to bring this little guy home. I figured he'd at least have my otos for company, and I had wanted to get some dwarf cories of some kind to live with the otos at some point anyway. So I'll get him some friends as soon as possible!

He's so cute! I love him already. He's swimming about and exploring the tank now

 

[FishGuest5123]

We will start with the tank, your tank has a base I think of 15"x15". Traditionally breeding tanks are made long, They are Twice as long as they are high and deep ( eg 24"x12"x12" ) The reason for this is to give the fish room to run. I would never put Corydoras into something smaller than this tank 15 gallons. The shape is important. You have managed to get these guys to spawn, great and we can work with what you have got. Because of the shape and the fact that everybody is on top of each other, the parents have to come out. The baby guppies can stay there they are fine.
I would normally move gavel away from one end or the front of the tank by about 3 inches this gives a section of bare bottom. Important for cleaning and observation. Any food you put into the tank is a suspension it will fall to the base of the tank and will end up at the lowest point, the bare base of the tank. The rest of the base doesn't need to be disturbed, just syphon from the bare base you will see material draft down as you syphon. Only do your normal water changes, make sure you rinse the sponge filters, don't have the filters running to hard.
Feeding egg yoke has been described elsewhere. But use some cotton an old singlet or any cotton you have experiment with different material. The idea is that for new fry the particle size of the egg yoke should be so small you can't see it with the naked eye. The suspension in the tank should look like milk. It only takes a tiny bit of egg to achieve this. That suspension will dissipate into the tank the young fish will pick up those tiny particles. I only ever feed twice a day. Morning and night.
I have said it is possible to leave the parents in the tank. I have done this with a tank 48"x18"x18'' The tank was heavily planted at one end. Once the fish stopped spawning you feed them. The next morning they spawn again and you feed them once the fry hatch they migrate into the gravel bed where they are largely safe, feed egg yoke which drifts to all parts of the tank the fry get food. I have explained why egg yoke feed this way is so good, remember this is first food, I would feed this for one to two weeks depending on the setup and number of fish. Ask more questions if you like or don't understand what I have written.

 

[CassCats]

Re: egg yolk
I'm hesitant with it in tanks or containers simply aerated as that would spoil very quickly, and any ammonia would kill fry easy.
Daily water changes are done, but no filter until these guys are a few weeks old on my end. The hatchery and nursery is simply aerated and heated. Egg yolk would spoil super fast as fry dont always eat everything either.

Great as emergency feeding, but its not the best first choice imo.

 

[FishGuest5123]

Just curious... you questioned me for using bare bottom and said you wouldn’t do it. Yet, you say here that you leave a bare bottom In half. I’m confused?

 

[FishGuest5123]

We will start with the tank, your tank has a base I think of 15"x15". Traditionally breeding tanks are made long, They are Twice as long as they are high and deep ( eg 24"x12"x12" ) The reason for this is to give the fish room to run. I would never put Corydoras into something smaller than this tank 15 gallons. The shape is important. You have managed to get these guys to spawn, great and we can work with what you have got. Because of the shape and the fact that everybody is on top of each other, the parents have to come out. The baby guppies can stay there they are fine.
I would normally move gavel away from one end or the front of the tank by about 3 inches this gives a section of bare bottom. Important for cleaning and observation. Any food you put into the tank is a suspension it will fall to the base of the tank and will end up at the lowest point, the bare base of the tank. The rest of the base doesn't need to be disturbed, just syphon from the bare base you will see material draft down as you syphon. Only do your normal water changes, make sure you rinse the sponge filters, don't have the filters running to hard.
Feeding egg yoke has been described elsewhere. But use some cotton an old singlet or any cotton you have experiment with different material. The idea is that for new fry the particle size of the egg yoke should be so small you can't see it with the naked eye. The suspension in the tank should look like milk. It only takes a tiny bit of egg to achieve this. That suspension will dissipate into the tank the young fish will pick up those tiny particles. I only ever feed twice a day. Morning and night.
I have said it is possible to leave the parents in the tank. I have done this with a tank 48"x18"x18'' The tank was heavily planted at one end. Once the fish stopped spawning you feed them. The next morning they spawn again and you feed them once the fry hatch they migrate into the gravel bed where they are largely safe, feed egg yoke which drifts to all parts of the tank the fry get food. I have explained why egg yoke feed this way is so good, remember this is first food, I would feed this for one to two weeks depending on the setup and number of fish. Ask more questions if you like or don't understand what I have written.

Nice write up! Good info on most.