Hello All,

Can someone help with very strange Corydoras paleatus behavior?
I have a 5 G tank where I am trying to raise about 40-45 cory fry.
In this tank have to batch of fry (2 week difference).
Out of 200 eggs then wigglers, I was able to raise about 43 fry (4 month). Some of them are 1.5" and "fat" but some of them still stay in there 3-4 week size 1/4". I feed them microworms and some crashed Hikari sinking wafers.
All this was going well, up until last night. I noticed that some of my fry can not stay on the bottom, it looks like a fish treys to swim down, but "air bubble" takes them up.
I did emergency 40% WC, I added air stone. Temp always 78F
This tank has also internal sponge filter, and sand.

All 3 odd swimming fry died this morning.
Now I see almost all my fish has very strange behavior and look.
Right around gills and under head, I think all fry has pink coloration, and they don't eat.

Does anybody know what this may be?

Thanks
Aram

Thats a lot of fry for a 5 gal tank, and sounds like they are suffering from poor water quality. you should be doing small water changes twice a day with that amount. When I am raising fry, especially that many I use a 20 long and do water changes daily.

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Thanks for reply.

I do about 40-45% WC every Sunday. I guess it's not enough
Unfortunately I don't have room for 20G right now, is there anything that I can do to save some of this fish?

I noticed one or maybe more fry start having a fin rot

Thanks

Start doing water changes daily, it will help. If you have a main tank you should be able to move the bigger ones to it depending on what you have in there.

__________________
SUCCESS IS MEASURED BY YEARS, NOT MONTHS!!!
220 Tank build
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What about fin rot, do you think it will go away by doing WC?
Or I need to use Melafix etc.

Thanks

Good clean water will help fin rot. If you use meds with cories you need to use 1/2 doses as cories don't tolerate it that good,

__________________
SUCCESS IS MEASURED BY YEARS, NOT MONTHS!!!
220 Tank build
http://www.aquariumforum.com/f15/sta...late-3253.html

Thanks Susankat!

All work out well, I was afraid that I will loose all cory fry.
I had about 10% loss.
Now Fish is very healthy and always hungry!
I did not use any medications, all I did WC (30-40%) every morning for about 5 days. Now I do it on every other day ...
Works very well, the only problem is that, now I have extensive amount of brown algae in this tank. Have you seen this problem before before?

Thanks again!

I love corydoras paleatus- DO you have any videos of the spawning behavior?

Hi,

Sorry I don't. Tank is planted, so there is not much to see.
You can look at youtube, I have seen many cory videos there.

The tank isn't well established and that is why you are seeing the brown algae. It will go away on its own but it does take time and patience. Since you don't have enough room to add any more fish that would eat it, I would suggest to keep wiping out as much as you can get when you do water changes.

__________________
SUCCESS IS MEASURED BY YEARS, NOT MONTHS!!!
220 Tank build
http://www.aquariumforum.com/f15/sta...late-3253.html