Corydoras Behavior

[Trevor Waddell]

I have had my emerald green corydoras around two months now and I have noticed odd behavior. Instead of staying at the bottom of the tank in search of food they perch on top of a large rock in my aquarium for long periods of time. Does anyone understand why?

Thanks!

Trevor

[SugarBassJoe]

My hasbrosus corydoras do this on top of an anubias, each on their own leaf, my best guess is that they're resting. They do it periodically and are active the rest of the time, seems normal behavior to me.

[Trevor Waddell]

Also whenever I feed they stay on the rock and don’t notice them searching for food. Should I be worried they aren’t getting to eat?

[nabokovfan87]

On 9/16/2022 at 11:15 AM, Trevor Waddell said:

Instead of staying at the bottom of the tank in search of food they perch on top of a large rock in my aquarium for long periods of time. Does anyone understand why?

Corydoras like "shelfs" if that makes sense.  If you're familiar with catfish / shark behavior (I am by no means in any way) something that great whites do and most catfish tend to do is try to be out of the way.  They don't want to get attacked from underneath and so they feel much safer when they have their belly against the bottom of the substrate.  They also camouflage similarly, bright belly helps block out predators from seeing them underneath, dark sides and body help them to be difficult to see from above.   Alright.... so, this is "very normal" behavior from what I have seen and to me it's a sign that the Corydoras feel safe enough to interact with your scape in this manner.  It also means that is the spot they have chosen to hang out because of flow. That is where they are resting to taking in oxygen and just recover. 

You might also see eggs around this rock, typically underneath or on plants near this region.  I would verify those rocks won't fall if nudges just to make sure something like that won't cause an issue.

When I had the ziss bubble bio installed, The corys, amanos, and otos all sit on the top of it.  This is very common for a variety of fish 🙂 .
 

On 9/16/2022 at 11:40 AM, Trevor Waddell said:

Also whenever I feed they stay on the rock and don’t notice them searching for food. Should I be worried they aren’t getting to eat?

Not at all.  My black corys I almost never see them eat.  The two fry that grew up in the tank are more comfortable and I do see them eat.  If you see bellies full, they are fine. If you see sunken bellies, then you'd want to treat with meds for internal parasites.  They will typically only eat off the substrate, but if you have a large flat surface you can feed them there.  Let's say that rock was 4x the size, I'd expect them to eat there.  The behavior of them not eating there isn't an issue or a good or bad sign.  You can try to feed them just after lights go out as well.  Drop in some food, then sit in front of the tank for minimum of 15 minutes.  You should see some of the fish eating.  This gives the fish time to smell the food in the water and to get used to having you around the tank itself. Then they become comfortable, and then should come out to eat.  Some corydoras won't eat with the lights on and can be much more active at night.  My pandas are very much active when the light is on, but then in the herd there are some of them that are much more active after the lights turn dim!  My black corys rest all day, during the lights out they are a bit more active and show behaviors only during those times.
 

Edited September 17, 2022 by nabokovfan87
typo

[Trevor Waddell]

On 9/16/2022 at 2:10 PM, Pepere said:

About 2 weeks ago I did a water change using a different brand of water conditioner and 2 of my Emerald Green Cories died within 15 minutes or so.  As soon as I saw them in stress, I transferred all five to another tank.

 

The three cories that survived have definitely not been themselves for the past two weeks barely swimming around and barely eating.

 

Last night was the first time I started seeing normal frolicking and feeding from them.

 

perhaps they had injuries and were conserving energy, or perhaps the whole emergency move was psychologically traumatic for them..

 

have you noticed this wnith your from the beginning? Or is it new?

Yes, as soon as they were added they liked sitting in the rock together. Thanks for the input!

[Guppysnail]

My Pygmy cory use a dwarf red lotus. Everyone takes seats on a leaf for town hall meetings and hanging out. 
My panda Cory use a specific anubias and my Melini cory use twisted branches on spider wood. Each group finds its clubhouse area to hang out in. 

[Bev C]

 i have  panda cories in my main tank they are active when the lights are on but they will not eat  they swim going up the wall or and playing  in the stream flow of the power head  ,,  but they eat  and plenty their bellies are nice and round  but they like to eat at night or when lights are out .. usually i feed right before bedtime or  very early morning before timer and lights come on for the day ,, They do not sit on any plants yet  Do not have any big enough to sit on yet  but they set on my rocks and sponge filters 

I just got pigmy cories yesterday they are in my smaller tank till they grow out  a little  before safely adding to my main tank  they was laying on top of the guppy grass  and box filter ,, My small tank has sponge filter and a very small corner box filter ( to hold my purigen  and matrix  , filter floss )    can not tell how they eat yet they was just settling in their new  home ,, 

[Robstar]

My corys also seem lazy during the day, often staying in one place. But I noticed when I get up early to go to work, before the lights come on, I see them actively scavenging. My guess is they like the cover of darkness to feed.

[nabokovfan87]

On 9/18/2022 at 7:04 AM, Robstar said:

My guess is they like the cover of darkness to feed.

Yep! Very much so, they feel safer at those times.