If the fry are in an established tank with no other fish...

[chloespeaks]

do I need to feed them? Or are the protozoa from all the live plants and dead matter enough to feed them into the next week or so?

Last week, the cold temps dropped the temps in my tank and after a large water change, my corydora unexpectedly spawned. I happened to have a smaller (and not corydora ideal) tank that was cycled, planted available with only 2 nerite snails in it, so I put about 20 of the eggs into that tank. A few days later about 15 of them hatched and I saw occasional fry darting up and down. I heard that they don't need food for the first 2-3 days and conflicting information about what to feed after.

Now 4 days later, I have only seen one live fry yesterday and have removed 2 dead fry. I live in a small apartment in the city, so can't seem to lay my hands on any microworms or even frozen baby shrimp (though I will go today to a Petco after I pick up my daughter from school). I've done water tests and changed 20% of the water twice - pristine conditions. Should I be worried? I don't see any of them at all? I just took a few micropellets that I keep for the neons in the main tank and crushed it into a powder and put it into their tank, by my worry is that since they are cory fry, they won't go to the top to feed. The tank (not idea for corys) is a 6 gallon Fluval Chi so it is very tall and narrow.

[JamesFish]

The fry from cory's I very rarely raised with success largely due to lack on effort on my part.

Have a look on forum a very good article exists about it un the cory section.

The first few days cory fry and many others have what is called an egg sack and this is what they feed of. Once that is gone however 2-4 days if memory is right they need to eat and require very fine food.

Link here to what you most likely need to know

http://www.planetcatfish.com/forum/view ... f=6&t=8726

[bekateen]

I've had good luck with albino corys, and I feed them a finely pulverized mix of dried fish foods: regular fish food flakes, sinking pellets, algae wafers, freeze-dried worms or shrimp. My opinion is that for this to work, you need to really pulverize the food until it is so smooth that it feels almost silky if you rub it dry between your fingers. I use a mortar and pestle to get it so fine. I feed the fry this 2-3 times per day. If your tank has really good circulation, the powder will sink to the bottom and the fry can feed down there, without having to come to the surface. If it doesn't sink for you, take a small pinch of the powder and get it wet before you add it to the aquarium, then it will sink.

As far as yolk sacs, my corys don't have very large yolk sacs, and I suspect they start feeding within a couple of days of hatching. So if you've gone 4 days without feeding them, I suspect they've started dying. On the other hand, my trilineatus corys don't like to be exposed when really young, so I will go 2 or 3 days without seeing them in the tank because there are hiding places in the tank (logs, plants, etc), then out of nowhere one day I'll see one or two fry, then none for a few more days.

If your tank has hiding places, I wouldn't worry about not seeing them. Just add a little food 2-3 times per day.

Good luck!
Eric

[chloespeaks]

thanks for the help bekateen and JamesFish,

I'm not that hopeful that I was able to save them - I'm obviously no expert on fish fry. Since the end of Day 4, I've been putting in pulverized Hikari brand micropellets and freeze-dried daphnia, a little a few times a day, but I wasn't able to get them Hikari First Bites or frozen baby brine shrimp until today,which is Day 6. Just put in the baby brine shimp a few hours ago.

I'm not going to give up on them - I'll go another week or so of just feeding, but I haven't seen any fry for about 3 days...

I feel really bad about this; I did the best I could.

[bekateen]

Hi Chloespeaks,

You didn't say whether your tank has any hiding places. If there are none (no wood, no caves, no ornaments, no plants, etc), then you most likely have no fry left, unless they camouflage well with your substrate. But if you have hiding places, you may still have fry left.

Eric

[chloespeaks]

Good news! This morning we saw three live fry when I fed them a sprinkling of frozen baby Brine Shrimp.

They are really disarmingly still - they lie in the cracks between the gravel and don't move much at all. Having had guppy fry previously, I would have expected a little more darting around

Eric, yes there are many hiding places for these fry. I have spent 10-15 minutes looking at the tank without seeing anything move.

[Corycory]

I've raised mine without problems on baby powdered food. But I soak it first in a small container with just a bit of water, then use a syringe to pick it up but I squeeze all the water so just the wet powder is left in the syringe(when you turn the syringe upside down the powder settles). Then I carefully place the powder in little piles on the sand so it doesn't float all over the tank by the flow. The baby corys than all gather around the food.

This can really foul the water without daily water changes and feeding just a few fry is even harder as they are not very opportunistic when very small, hide most the time and may not find the tiny bit of food one would use to feed just a couple of fry.

I have a modified hang on box which has water flow in and out all the time from the main tank and it worked great for raising just 3-4 fry, cleaning left over food a couple of times daily as it becomes like "fluff" on top in 24 hrs if not eaten or removed.

The gravel type of bottom you have is going to be hard to keep clean with cory fry and will most likely get polluted. I would not trust any tests when it comes to fry tank water.

[Karsten S.]

Hi,

another easy but nonetheless very good alternative for the first days is filter mud.
I (and many other cory nuts) use it for cory species (like C. hastatus, C. pygmaeus) that are after hatching just too small to manage brine shrimp nauplii or I use it sometimes also over a week-end when I'm not there. In the mud there are lots of microorganisms and it doesn't charge the water that much.
The most frequent error in raising cory fry is to give them too much food.
It is normal that cory fry tries to hide in the first days, in the parents tank you quite often only see them only once they have reached 1- 1,5 cm.
I usually put some dried leaves (beech) or java moss in the fry tank where they can hide and search for food, snails are also good companions as they eat the superfluous food and keep the surfaces free of bacteria growth (most important with bare bottom).

Cheers,

[dw1305]

Hi all,

another easy but nonetheless very good alternative for the first days is filter mud.

I agree with Karsten, and if we had "likes", I would like their post.

I usually put some dried leaves (beech) or java moss in the fry tank where they can hide and search for food,

I also like filter squeezings, Java moss and dead leaves as a food source for small fry, and I always have MTS and Asellus as "Fry Janitors".

I've had a look at quite a lot of filter mulm under the microscope now, and a common factor seems to be that it contains a lot of Rotifers.

Seeing your photo I'm a Hornwort (Ceratophyllum) fan as well . Have a look at Apistomaster's posts here:<"http://www.planetcatfish.com/forum/view ... hp?t=29511">.

snails are also good companions as they eat the superfluous food and keep the surfaces free of bacteria growth (most important with bare bottom).

I like a substrate and I much prefer sand to gravel, the fry can't get stuck in the gaps between grains.

cheers Darrel