HELP MY CORY FRY!

[CoryDan]

Hi All,
I am a first time bronze cory breeder,
have had success hatching my first
spawn (managed to save 18 eggs in total 16 of which were fertile) but now have run into troubles.
At 7 days after hatching (yolk sacs were visible for about 3 days) the fry have still shown no intrest in feeding and do not seem to be activly seeking out food. I have attempted to intrest them with First Bites and also Rotifurs (both disolved in a little tank water)
removing all food from tank 30-40 mins after attempted feeding.
Last night i noticed a few deaths and there is no change in behavior today.

I am using a 2Lt tank ph6.5 temp26'c with a sponge filter heater and java moss(no substrate)
Have been doing 30%-50% daily water changes from the community tank (ph6.5, temp24'c)
the only thing that i can think of is that the sponge filter was brand new and therefore no nutrients or that the temp change when cycling water is to great.
If anyone can share any ideas or suggestions as to the reason behing my poor little coreys plight i would really appreciate the input.

Thanks a bunch all

ps. just noticed there is a fresh spawn going on as i type.

[Karsten S.]

Hi,

the best food is newly hatched brine shrimp naupli, I have not yet found any catfish fry that wouldn't feed on this.
I raise all my corys in the first days/weeks with it.

As you need as least 2 days until you have hatched ones:
Take some detrius from the filter of your main tank into the fry tank and leave it there. They always find something to eat in it.
I would also recommend to add a thin layer of sand just enough to cover the glass and some snails (like this one: http://en.wikipedia.org/wiki/Red-rimmed_melania).

Cheers,

[MChambers]

Microworms are another good food for corydoras fry.

[CoryDan]

Thanks for the ideas!
I will give the sand, snails (have plenty of them in the community tank, Pakistani Loache love them) and the baby brine shrimp a go next spawn that i can save.
Unfortunately i didnt make it to the last spawn in time!!!

No change in fry bahavior today, lost a couple more last night...
Bad timing went away for the weekend and left them to fend for themselves!

[LughLamfada]

You will end up losing about 20-30% of your fry in the first few days. Out of the 20 or so you have, I'd say you can count on 7-10 making it to full maturity.

If they're not eating, try taking some baby brine shrimp (frozen will do) and defrosting them in a cup of water, then use an eye dropper or a plastic pipette to suck up some of the shrimp and gently (gently!) squirt it on the substrate near where the fry congregate-- like literally stick your hand in there, place the end of the pipette almost on top of the substrate and ever-so-slowly squeeze the bulb. Cory fry love baby brine shrimp and will eat them until their little bellies turn pink.

Once they're older, you can take a frozen baby brine shrimp cube and drop it directly into the tank-- it'll slowly sink then defrost on the bottom of the tank, leaving a big pile of food for the fry to root through.

[CoryDan]

I have just arrived home with a brand new eye dropper and am going to try the precision feeding right now!
couldnt find frozen baby brine shrimp at either of my local aquarium stores so i'll keep on trying rotifers for today...
(they dont seem interested at all though)
Tomorrow i will go for a drive and find a shop that stocks more feed.
Still about 8 of the little guys hanging in there at this present time.
Fingers crossed i can find some frozen brine shrimp asap although it may be simpler to grow my own by the looks of things.

Thanks everybody for the suggestions so far!

[Vlacek]

I'm not an expert on bronze cory but isn't 26C a bit high for them? I raise my c.venezuelanus (similar fish) at 24C. The higher the temperature is, the quicker water quality drops so might be an idea to go a bit lower, just keep it the same as in your comunity tank. Have their pectoral fins developed ok? I observed that although fry hatches, it's fins are not ok due to quality of water eggs were in (have problem raising c.hastatus)

[medaka]

When I was first started to spawn cories, I was informed by a long serving club member, whom had spawned quite a few types of tropical fish, that he fed his cory fry on a liquid marine invert food for the first 5 days or so. I decided to give it a go and I must say I had very little fry fatality. I still use this method especially on the small cory fry like Cory 'SP' C132.

It may well be that the 'invert food' actually feeds the tiny organisms that are found in the around the filter and in amongst the substrate of a mature tank and consequently they multiply in large numbers, and it is this that the fry feed upon? I really don't know, but as it works for me I ain't going to change from using it.

I usually feed my cory fry this for the first 3 or 4 days and then I add a small amount of powdered flake food to the invert food and feed this mixture for another few days, then I alternate this food with newly hatched brine shrimp. For very small fry I make sure that the brine shrimp is no more than 24 hours old, as I tend to think that the fry end up constipated due to the shrimps exoskeleton becoming hard and un-digestable.

[Coriequest]

Can you share the name of the product? Thx!

[medaka]

It all depends on what is available in the LFS or through fish club auctions at the time.
The product that I prefer is: Liquid invert food by Waterlife products
Although I do use a dry invert food by API if I run out of the liquid.
Like all first foods attention to water quality is a must.

[CoryDan]

Thanks to everyone for the help i now have a stable and functioning fry tank, after introducing a bit of crushed coral to help moderate the ph and keeping a good eye on nitrate levels all is running smoothly. (also invested in a more permanent tank setup...)
I have two of the original spawn left and they are going great! The 2nd spawn wasnt so lucky as i stupidly put a mystery snail into the tank... It ate all but one of the three day old fry over a period of 2 days! But the lucky survivor is looking strong! Very active although keeps distance from the two older corys in the raising tank.
The original spawning female cory has continued to spawn on a weekly or bi weekly basis for over 5 weeks but never more than
20-30 eggs in one spawn! IS THIS NORMAL? and why may this be occuring???
I have been hatching the fry in a floating net in the community tank then transfering them to the fry tank a day after they begin free swimming snd feeding rotifers and first bites! (no local shops stock bs eggs, micro worm or vinegar eels)
Once they are in the raising tank they seem quite happy and i am having minimal losss of fry at this point, just gotta keep an eye on the older ones to make sure they dont get any ideas about making their younger siblings into a nice snack!

thanks again for all the help ur ideas and input have been most helpfull!

cheers

[medaka]

Hi CD

(no local shops stock bs eggs, micro worm or vinegar eels)

It maybe worth your while joining a tropical fish society in your region. As well as being a great source of information, you will find that there usually is at least one person who keeps such cultures.

[corylady]

i breed trilineatus and orange lasers. i use a 5 gal. egg tank.eggs hatch, i sipk\hon them out w/a piece of air tubing to a 5 qt. ice cream bucket. i pour them in the 10 gal. fry tank. nothing in there but a sponge filter. i do periodic water changes using stress coat as i have good luck w/it. i feed them frozen baby brine i get from a small local pet shop that orders it for me. my growout tank has 150 juvies in it, 60 or so in the fry tank and eggs on the glass in the 5 gal. my spawning group is only9 or so. they spawn every 8-10 days. but talk to the pet shop owners to order the bbs for u. some will.