Corydoras sterbai eggs - moved to separate tank - questions

[Vorpal]

I put filter media, plus nylon over the little filter pump & I think it is still too much. I may try some other pets shops tomorrow. I did get some Liquifry, and started adding that to the tank. Hopefully, that will be enough.

The eggs have gone a sort of sandy colour. Does that mean they will hatch soon?

 

[Vorpal]

A few have hatched. They are really hard to see, but I got lucky and caught a fry moment with my phone.

 

[Martyn87]

Awesome! Whilst they are this young I would keep the filter off and just do daily water changes. You could just use a very small airstone to move the water about until they get a bit bigger, or give them something to shelter behind.

Get a micro worm culture little corys love these wrigglers and they provide a great source of live food for fry.

 

[Vorpal]

I put a piece of filter media in there from another tank, and a few plants.

I have turned the filter off. I did try to find an air stone the other day, but the pet shop I was at did not have any. I was thinking of making my own sponge filter but could not find the parts. I can try another pet shop or two tomorrow afternoon, but the market is pretty limited where I live.

 

[Martyn87]

Is the filter already cycled? The fry will create so little ammonia that you just need to make sure the filter stays live. I’d keep it in the other tank until the fish are a few weeks old, the fish will be fine as long as you do regular water changes. But a sponge filter is best for rearing and it’s a food source as well. As someone noted earlier almond leaves are good too and the fry could hide under them?

 

[Vorpal]

The filter is cycled. I keep some extra bits of filter media in the external filter for the mother tank, so I can use them to start new filter pumps or aquariums.

I went to some other pet shops yesterday, and found an air pump and air stone. The shop said they would order a sponge filter that was compatible with the pump, and that will be in on Friday. How does one cycle that sort of sponge filter? My normal approach is to replace 1/3 - 1/2 with media from a cycled tank.

The fry like the sponge in there. It's propped up on a suction cup which I put in there because it had eggs on it. The fry like to hide underneath it. I moved it accidently this morning, and there were suddenly fry scooting about everywhere!

 

[Martyn87]

What was the other sponge you referred to?

Any sponge filter should be compatible with an air pump?

You could just pop one of the sponges in your main tank canister for a week and it’ll likely pick up some bacteria then you can move it over to the fry tank as they grow on. Floating plants also help sap up ammonia.

 

[Gypsum]

My eggs are SOL. I think they got fungus and died. Hoping our fish spawn again soon and give us another chance. And they need to do it when we're around because we have things in that tank which will hoover up eggs in seconds.

I set up my hospital tank with a sponge filter, scraped the eggs out of the main tank, and then put them in the hospital tank. Didn't do much more than that. Did I miss something? What else could I have done? Hospital tank is circa 60l and I filled it about halfway.

 

[FishGuest5123]

Actually, they eat to the baby brine shrimp just like any other fish, yes they are bottom feeders, but they swim to all parts of the tank. Top, mid, and bottom. Sand isn't needed for at least the first week of a cory fry's life. Mine have bellies full with baby brine shrimp. Little pellets make the water foul.

Actually, I agree with @Byron. In Cory tanks the bottom should have a light level of sand. Bad bacteria grows on bare bottoms. This is dangerous for cories since they lay on the bottom. Now, in my goldfish nursery tanks I do keep them bare bottom because fish are not lying on bottom floor. All articles that I have read instruct you to cover bottom with sand.

 

[Vorpal]

What was the other sponge you referred to?

The sponge is part of one from an Eheim pump/filter that has an internal sponge.
You can't see the fry, but they like to hide under there.

 

[Vorpal]

This is from yesterday. It is the best picture I have so far. I have seen as many as 16, but they are still easiest to see when moving. Because this one settled on the thermometer, it has nicely put itself where there is also something for scale. The thermometer is about 4 cm (2 inches) across.

 

[Martyn87]

Looking good. I've always found that Cory's grow slowly...how many fry do you have now?

 

[Vorpal]

Looking good. I've always found that Cory's grow slowly...how many fry do you have now?

I don't actually know. I assume that I have not spotted them all at once. Even though they are getting easier to see, they are still hard to see when they hold still on the sand. I think somewhere around 22 - 25?

They're fascinating to watch. They look wiggly like tadpoles when they are on the move.