Bronze cory - Corydoras aeneus

Contributed by: David»13»

On: February 18, 2007, 3:22 am

Peaceful bottom dwellers that use whiskery barbels to find small food items in the substrate. They will shoal with other cory’s.

Contributed by: Casi»8»

On: September 30, 2007, 7:02 am

I was recently told I should have at least 5 cories in my tank. I am a little worried about over populating my tank. I am not even sure my three cories are bronze cories, but the picture is closest to what they look like.

I have a 30 gallon tank with 14 fish. 3 cories, 1 bristlenose, 4 neon tetra, 4 platy (2 male, 2 female) and two femal guppies.

When I first got the cory, they were very active and kept the bottom of the tank spotless. Now they huddle in a corner and never go passed the halfway mark and rarely even that far. They are pretty much on top of each other a all times and seem to be afraid of everything including the tiny neon tetra. They keep the area directly around them clean, but rarely swim or move from their corner and never when anyone is near the tank.

I am worried that something is wrong with them or that I am not doing something I am supposed to. I am new to fish tanks and not even sure I am feeding them correctly. I am only using tropical flakes.

Contributed by: admin»789»

On: September 30, 2007, 12:52 pm

Hi Casi,

Your tank won’t be over populated with more Cories. I kept more than 100 specimens of Bristlenose Catfish in my 81 L aquarium (because they breed there). As time goes by I am selling them, but I currently have at least 50 of them. When I am talking about reasonable crowd of fish, 4 Neon Tetras = not enough at all. These fish should be kept in the group of 10 at least. My personal experience.

Now to Cories. I assume only 3 potential reasons of such behaaviour; Inappropriate lighting conditions, inappripriate crowd, or inappropriate amount of fishes (Cories only). I’d bet on the second or third option.

I keep the Panda Cories and I can tell you that they are more active when there are 6+ of them in one fish tank. What’s more, they are very social and if you have 5 "old friends", they will hardly accept a new specimen. That’s why it is always good to buy 4-5 of them at least.

But the problem could have another cause as well. I also kept Bristlenose Catfish with Panda Cories and Pandas weren’t too active that time. When I removed all Bristlenose specimens the Pandas took over the entire aquarium.

I’d like to recommend you watching them when the light is turned off. Check if they swim through the tank or if they stay at the same place like always.

If nothing changes, try to divide the aquarium with a divider or buy another aquarium just for Cories. This option will work (nearly) for sure and you’ll (probably) get what you want; Happy Cories. BTW, this is what I did for my Cories. They’re now happy and they also laid eggs for a few times since they’re alone;).

Contributed by: Casi»8»

On: September 30, 2007, 3:51 pm

Thank you for your quick response. I got my cories when they were very small. I have had them about a month now. Do you think it is too late to add more cories? My bristlenose visits the cories a lot and they don’t seem to be afraid of him. I have noticed the cories on the other side of the tank when I come in to turn the tank light on and feed them. As soon as they see me, they swim right back to their corner. They do not clean the other side of the tank.

I am so new to this and really don’t know what I am doing. I change 1/3 of the water once a week. Last week I changed half and the filter because the water was getting cloudy. I have not done a full cleaning. I don’t know when that needs to be done or even how to do it.

I am still trying to find out if both of my guppies are really female. (bought in all female tank). What I have read, and the pictures I have seen are very contradicting to what I see when I look at them. This site is helping a lot but I have much to learn. Thank you for all your help.

Contributed by: admin»789»

On: October 1, 2007, 11:26 am

Hi Casi,

It is never too late to buy new Cories;). I found them to be the most beautiful fish at all. Buy 3-4 specimens at least.

Every fish reacts differently on humans. My own Cories don’t care about me when I am playing inside of their aquarium (maintenance, cutting plants, etc.), but Bristlenose Catfish are very scared when I do similar things in their tank. And when I kept Angelfish with Gouramis, they even came to my hands and tried to nip me:). I felt it a little;). It was so wonderful!

Maybe you just need to learn about them, learn their personalities and everything will be easier later;).

RE your Guppies: I just bet now, but maybe they’re hybrids? Some species are able to crossbreed. But as I mentioned previously, without images I am powerless.

Contributed by: Casi»8»

On: October 23, 2007, 3:35 am

I bought 3 more cories. One was so tiny, he barely had any color yet. The biggest of my older cories stayed pretty close to the tiny one. The three new ones were very active and went around the whole tank. The three older ones started following them around. All was well for about a week and then the tiny one became sick. First he stopped swimming then he turned completely white. I tried to heal him. His color got better and he even started swimming again a little. He died two days ago. All the other cories are still moving around the entire tank though. My bristle nose stays close to the cories most of the time and tries to get himself in the middle of their group. I have noticed when I turn the tank light on in the morning, my bristle nose and my tetras and the smaller cories are all terrible colors and look like they are dying. After the light is on for about 15 minutes their colors start getting back to what they should be. Is this normal? The bristle nose is almost yellow when I first turn the light on and the neon tetras have no color at all. The cories also have a yellow tint when the light first comes on.

Contributed by: admin»789»

On: October 24, 2007, 12:28 am

Hi Casi,

Fish may change their colours depending on the light conditions.

Anyway, I recommend you to buy some basic tests; pH test, dKH and dGH test, and NO₂ test. For your aquarium, the pH level should be between 6.5 and 7.2, dKH between 4 and 8, and dGH should be more than 6 and less than 20. The NO₂ test is the most expensive one out of those which I mentioned.

So if all tests say that the water is normal, then you don’t have to worry about colours changes.

I remember when I kept Angelfish and Gouramis, they were changing colours as well.

Contributed by: Sandy»2»

On: January 24, 2008, 5:52 pm

I have a 10 gal tank at my work ( the office mascots) I currently have 2 baby molleys in the tank along with a donated Pepper Frekkled Cory. He’s pretty chill in there by himself, but I wonder how he would react to having another cory or two added to the tank, according to the previous owner he’s been alone in the previous tank for quite some time, several years actually. He’s really active part of the day and calmly sits and hangs out with the baby mollys. How many fish can I have living happly together in a 10 gal tank?
I’m a little clueless about how many without overcrowding.

Contributed by: admin»789»

On: January 25, 2008, 12:19 am

@Sandy: I’d use the calculator which we have here firstly. Also I’d use a 10 G aquarium for small fish only. It depends on the fact if such fishes do well in groups or if they need some territory.

Contributed by: Neervana»9»

On: April 4, 2008, 1:52 pm

Hi, I have just bought a bronze cory! He is really tiny, no more than half a centimetre - is this a baby cory? If so, what should I feed him? I have algae wafers, I have krill, live bloodworm, river shrimp, brine, daphnia, tubifex, tetra min and tetra pro. I tried to drop some JBL catfish pellets but he couldn’t eat it, it was too big for his mouth so the guppies got to it first! I'm really worried in case he doesn’t get any food, he’s such a character he’s my favourite already! Please help. Thanks guys!

Contributed by: admin»789»

On: April 5, 2008, 12:08 am

@Neervana: Yes, a such small Cory is a baby Cory:). I breed Cories and therefore I know what to feed them:). Check the following pictures (as links), you will see what they require.

Sera Vipagran, Sera Small granules, Sera Granules, Sera Tablets (crush them into small pieces).

BTW, I think that you bought a very small specimen. It’s recommended to buy bigger specimens as they’re more resistant to any change of their environment.

Contributed by: Neervana»9»

On: April 9, 2008, 3:41 pm

Update on my baby cory! He is doing so well, he is swimming around everywhere and he has learnt to come up close to the side of the glass, he knows I will give him food! I have been crushing pellets and wafers to feed him and I bought live bloodworms - really micro tiny ones and let them free and they bury into the sand and he digs them up and eats them! He has coloured up brilliantly! He has metallic goldy-greeny hues on his "cheeks" that make him look so cute! I have a new 400L tank and it has been a week since I have put five guppies in it and two small angel fish and that bronze cory. Should I do a water change tomorrow? I checked for ammonia in the water with an api test kit and it remained colourless. Meaning no ammonia.

Contributed by: admin»789»

On: April 10, 2008, 1:26 pm

@Neervana: Periodical water changes are necessary. However, if your water contains no ammonia and if your aquarium is 400 Litres of water (+-) with only a few fish, then it is not necessary to change the water often. Maybe 1 change each 2-3 months will be OK.

Good luck:).

Contributed by: Neervana»9»

On: April 26, 2008, 11:48 am

My baby bronze cory is growing very quickly! Already he is about a couple more centimetres. His feces are dark brown. Is this healthy?

Contributed by: admin»789»

On: May 6, 2008, 5:06 am

@Neervana: Looks like you’re feeding him/her too much, or it has a lot of food in the tank (algae for instance). Anyway, I don’t think that it’s unhealthy what is happening. Give him less food if possible.

Contributed by: Atlantis Child»2»

On: July 27, 2008, 12:14 pm

I have found that broze corys aren’t nearly as hardy as their albino variant. Has anyone else noticed this? Of course, it might have something to do with the quality of them around here, but I’m not sure. Only my first bronze has done well. She is a round and nice colored little girl.

Those 2 I got later had not great color, grew pale and did not reach adulthood. They did the worst of all my species of corys.

Contributed by: admin»789»

On: July 27, 2008, 11:26 pm

@Atlantis Child: As you already mentioned, it all depends on quality of these specimens. Some may be hardy, some don’t have to.

I am not sure how experienced you are, but doing a basic water tests can help you which way to go. Maybe there’s something in the water which they don’t feel comfortable with.

Anyway... I breed Panda Cory’s. Long time ago I bought 5 new specimens in order to bring new blood into the family. They all died as time went by. But the old ones kept breeding and living without any disease/problem.

For further questions, visit the forum, please.

Contributed by: Alvin»7»

On: July 30, 2009, 2:43 am

One of my cories have died and I only have 3. So do I have to add another? Because the aquarium shop that I bought them from last time has no stock already, so can I just keep 3 of them while waiting them to recover their stock?

Contributed by: admin»789»

On: July 30, 2009, 9:12 pm

@Alvin: Naturally, you can keep only 3 specimens. However, add others as soon as possible since Cories love to be kept in groups.

Contributed by: Carr»1»

On: August 13, 2009, 10:50 pm

Why are my bronze cories are so shy? They only come out when no one is watching the aquarium. When I look close to the aquarium, they frantically rush to hiding and once I left, they only come out looking for food (I watch them from afar).

Contributed by: Alvin»7»

On: August 13, 2009, 11:00 pm

Thanks for the advice. Another question, can cories be kept with chinese algae eater? I'm afraid the algae eater will harass them. Because they will feed at the same level.

Contributed by: admin»789»

On: August 15, 2009, 8:53 pm

@Carr: Even though Corydoras species are timid and shy fish, they shouldn’t hide all the time. Since you haven’t mentioned any details about your fish tank, here are some suggestions:

1) Try adding more plants into the aquarium,
2) Try to subdue the lighting,
3) The colour of the substrate is very important; it shouldn’t be completely white, it shouldn’t act as a mirror,
4) Try introducing more specimens into your aquarium as Corydoras feel much better when they’re kept in large groups.

@Alvin: I wouldn't keep these two species together in one tank. Some say they may get along well, some say they won't. So... It's always risky.

Contributed by: Gabbie»2»

On: January 19, 2010, 7:00 pm

Hi, I am new to tropical fishtanks. I have a 110 l fish tank with 6 tetras and a bronze catfish. I had 2 chinese algae eater and another bronze catfish as well but - and this is my problem - they have died. I can not think of a reason. And now my other catfish is dying. At least I think.When I see it move, it is swimming on its side and lying on its side. The water kept at 22 - 24 C. And also they did not clean the bottom at all. I am devastated as I had to watch them die and I really want to save this little fellow and would want more of them. This was my first group (the shopkeeper recommended these fish) and I am not sure if I want another... just to watch them dying... what do I do wrong? What shall I change?

Contributed by: admin»789»

On: January 24, 2010, 2:37 am

@Gabbie: There are plenty of things that could have went wrong. Firstly, is pH and KH (carbonate hardness) good enough to keep this species?

Also, keeping 2 specimens is way too hazardous! Corydoras is a fish that needs to be kept in groups. The more, the better!

Test the water in your aquarium and you will avoid all problems. If it doesn’t fit your fish’ requirements, change it or do all necessary modifications that will lead to happiness of the fish kept inside.