Baby corys - what now?

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Baby corys - what now?

Postby Reginald_Rat » Sun Apr 14, 2013 6:54 pm


My pair of bronze corys have recently spawned (for the fourth time) - after previous failures* I now have about 20 newly hatched fry. I feel I owe it to them to increase their shoal.

* No. 1 - left the eggs in community tank - all got eaten
No. 2 - moved the eggs into a net suspended in the water - eggs hatched, but then the fry were eaten through the net (not sure who by or exactly how)
No. 3 - placed eggs in small container within tank and changed water daily - eggs succumbed to fungus.
No. 4 - placed eggs in small net within larger net suspended in tank, and removed any fungusy eggs each day - result = 20 babies.

Now not sure what to do - I have a second tank, but that is full of guppies. They wouldn't last long in the main tank (although a couple of baby oto's survived last year - one of them is watching me as I write this...). I can probably leave them suspended in the net for the timebeing... any thoughts? I don't have room for another tank!

Second thing, I have no idea what to feed them. I believe you don't add food straight away because they use their egg sacks. They are one day old but will presumably want dinner soon.
Any help would be gratefully received.

(N.B. I posted last year about having oto eggs - Carylnz suggested they might be catfish eggs - they were...)
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Re: Baby corys - what now?

Postby Carylnz » Sun Apr 14, 2013 10:08 pm

Angelfish are good at sucking fry through a net!
Usually methylene blue or acriflavine need to be added to the water to stop the eggs fungussing but you have managed without so that's good.
When the fry hatch, they drop to the bottom and absorb their egg sac for a couple of days. Some people squeeze a sponge filter over them to build up the mulm on the substrate (unlike most species where it is vital the tank be super clean, corys seem to like muck) as the fry will eat the microscopic greeblies living in the mulm. They can also be fed microworm or newly hatched brine shrimp. I think it is Tetra who make a liquifry food for egg layers too.
The fry grow quickly and are about 7mm long in 1 month.
Can you make a low cave from rocks, or put in a small tube big enough for the fry to fit into but not any adult fish? Otherwise, a heavily planted tank is ideal for them as they can hide in the plants and roots and have plenty of food getting trapped there too.
You could try separating them into a plastic container and float it in the tank (I have a 2L ice cream container in mind but I don't know if your ice cream comes in the same shaped containers as ours- about 16cm sq and 9cm high). You would need to do daily water changes to keep ammonia and nitrites down but if you have a source of green water (any stock troughs around?) they would eat that, or add liquifry food.
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Re: Baby corys - what now?

Postby Reginald_Rat » Tue Apr 16, 2013 10:35 pm

Thanks for the advice. They are now all in a tub floating in the main tank eating liquifry. All look quite happy at the moment.
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