Cory eggs in sand

[Adamsh]

Hi all,

New to the forum, and come with a question

My Julii Cory have been laying eggs, over the last week a couple haven't left each other's side, and seem to be laying 5 at a time randomly.

I initially purchased a breeder net and put the leaves that had eggs on into it, I left the eggs on the glass as I was sure how to move them.

2 of the eggs hatched, the rest went bad. After realizing I had 2 tiny fry I went and purchased a small tank for them.

Tonight they have deposited 5 more eggs. 3 on the glass and 2 on leaves. I followed instructions on how to move the eggs off the glass and stuck them to the side of the fry tank. Unfortunatly 2 fell off into the sand.

Now for my question, will the 2 eggs in the sand hatch? I tried to put them back on the side but they had sand grains stuck to them and woulldnt stick.

I have added 1 drop of meth blue to the tank , it is an I litre tank but only has 2 litres of water in.

The 2 fry in it are currently 4 days old and are being fed twice a day on liquifry right after a 50% water change using water from the main tank.

Thanks for reading

[MarlonnekeW]

Congratulations with your baby cory's!

I'm not sure if the eggs will hatch in sand. When I had a problem with falling eggs, I used a small net (the same that you use for catching fish). If you gently move the net (for example up and down) close to the egg, the egg will start to move/swirl upwards. This will allow you to catch the egg with the net and put it with the other eggs, without damaging it.

I'm a big fan of using a netbreeder. I use it for about 2-3 weeks in the aquarium were I keep the baby's before releasing them into the tank itself. I think the risk of damaging the eggs is lower if you put them in the netbreeder than if you stick the eggs to the side of the aquarium, because the netting is open you'll still have a good waterflow and it's easy to feed the baby's because you can put the food very close to them, so you can be sure that they have enough to eat.

I always put in a small piece of catappa leave with the eggs. This will prevent the eggs from going bad and it will provide shelter for the baby's.

[Adamsh]

Many thanks for the info.

She laid 16 eggs in total tonight. I moved them from the glass and put them on plant leaves (with stems) which I then placed in the fry tank. The eggs seemed to stay in place when on the leaves.

They fry tank doesn't have a filter, but had an airstone for water movement.

I think I'll get the breeder net out for the next batch.

Here's a photo of the main tank with the little fry tank on top.

I've got a video of them fertilizing as well which was pretty cool

[MarlonnekeW]

That looks great. I guess you can also put the netbreeder in the main aquarium. Then you won't need a separate fry tank and if some of the food will get through the netting, it will be eaten by the other fish.

Personally I had some remarkable experiences with cory eggs. One time I'd bought new floating plants and because I wasn't sure the new plants would grow in my aquarium, I put the old ones in a small bucket with tap water, as backup. Normally my corydoras panda would put their eggs on the glass, so I didn't check the plants. One week later 50 (!) baby cory's were swimming in the bucket, with normal tap water, no filter, no air stone, no water change etc.
With my pygmaeus I had a similar experience; I put some old plants in a bucket and a few days later I had a group of baby pygmaeus swimming in the bucket.
I wouldn't do it this way on purpose, but it looks like cory eggs can even hatch in bad circumstances.

[Adamsh]

I seem to have lost one of the 2 hatched fry, by lost I mean cannot see anywhere.

It is possible it's just camouflaged by the dark sand, it took me a good 10 minutes to find one of them, and even then I had to turn the air pump off. I'm 100% sure he hasn't been syphoned out as I am extremely ice in checking everything that comes out of their little bowl.

I was hoping they get some size to them before the new batch of eggs hatch, would be nice to identify the first 2 Cory fry I have ever had.

[MarlonnekeW]

In my experience, baby cory's can be hard to spot, because especially in the beginning they are pretty shy and like to hide. On the other hand, they are also not easy to raise, so losing some is (unfortunately) normal.

[Adamsh]

I've managed to get some frozen baby brine shrimp . I put some in yesterday and also this morning but haven't seen it eat any.

As I only have 2 fry (one a week old, other a couple of days) I'm worried about water pollution. I change 50% of the water twice a day via some air line hosing. but am always worried about sucking a fish up if I get too close to the sand.

I'll be even more worried once the other 13 eggs hatch. How long will it take for the unbeaten bbs Start causing problems. Also, as the little packs are too big for 2 fish I put the defrosted pack in the fridge, what's the average shelf life before I should defrost more?

Can I feed them bbs from the start or are even they too big. I did start off with liquifry and also got some JBL fry powder food but haven't used it.

[MarlonnekeW]

I always gave my baby cory's baby food, for example Tetra baby. I used a small plastic cup, put a bit of (tap)water in it, together with a bit of food and let it mix for a minute. Then I took a syringe (without the needle of course) and sucked up a bit of the mixture and squirted in on the bottom of the netbreeder (or in your case the fry tank). The rest of the mixture cannot be used, because it will go bad very quickly, so you'll have to throw that away.
I fed the cory's this way twice a day. Before I put in the new food, I took a bit of flexible pipe (the sort you use with an air stone) to remove all the left-over food from the last feed (in the same way that you can clean the bottom, but with a smaller pipe, so you won't remove so much water). With this system, I always did 'normal' waterchanges (once every 2 weeks). The netbreeder was in my 40 liter shrimp aquarium.

I might look like the cory's are not eating, because there will be some leftover food, but mine where growing anyway so they probably won't eat much in the beginning.

I hope this might help.

[Adamsh]

Great, thanks for that, I was using an airline hose to change the water, already sucked one little fishy into the bowl and had to pipette him back.

In other news, the eggs on the sand are starting to hatch, and they are very active. The eggs on the leaves haven't moved yet but I expect them any time soon.

Where the eggs on the sand were not stuck to anything, it resulted in the little fry swimming around with eggs on their heads for a few minutes.

https://youtu.be/nYEhAUmSDiQ

https://youtu.be/0X99pPqsDSI

[bekateen]

Hi Adamsh,

When my corys lay eggs, I transfer them to a 2.5gal plastic aquarium outfitted with only a thin layer of sand on the bottom, a small sponge filter powered by an air pump which isn't very strong, but it's strong for this little tank so it provides really good aeration, and some Java moss (which is helpful but not critical); you can see the tank here: http://www.planetcatfish.com/common/my_ ... e=bekateen. I dump the eggs straight into the tank, which means most of the eggs fall straight to the sand. Most of the time, I don't add any anti-fungal medicine, and I get pretty good hatching. Some eggs fungus, and believe it or not, some of those still hatch, although definitely some don't hatch too.

To feed them, I get several normal aquarium foods - about a tablespoon full fish flakes, an algae pellet, and if I have them, about a teaspoon of freeze-dried worms or shrimp or New Life Spectrum Thera A+ 1mm pellets (I have no exact recipe for this; it's mostly flakes because they are the cheapest in price, and the other foods are added according to whatever I have around). I pulverize these together in a mortar and pestle until they are so fine, they feel like silk if I rub some between my fingers. To feed the fry, I simply dip my finger into the powdery mix then sprinkle it into the tank. The aeration causes the powder to sink to the bottom of the tank, and the fry take to eating it as soon as they are able to feed. For me, this has been a great first food.

If you try this, you'll find that it's really difficult to overfeed them, since not much powder sticks to the fingertip at any time. But it also means you'll have to feed them 2-3 times per day (I feed mine in morning, after work, and at bedtime).

If you're having trouble seeing the fry, hold a flashlight right against the tank wall, right at the level of the sand, beginning about 3 days after the eggs were first laid. You should see tiny (about 1-2mm) almost transparent wrigglers squirming along the sand; in my experience, they tend to congregate with each other, and they hide under my sponge filter or in the Java moss, or in the corners of my tank.

Good luck, and have fun.

Cheers, Eric