Do cory's eat algae?

[Corylover]

My cory has been acting a little strange lately. She has been swimming up and down at the glass. She has not done this before and I was wondering if they ate algae cause there is a little patch left on the glass after my clean up. She does'nt seem to be interested in the food too much but her partner is. Is she ok?

[andywoolloo]

my female cory will swim up and down on the glass when she is cleaning it to lay her eggs. Have you seen eggs? My cories do not eat algae or not much that I am aware of.

But the females on the glass is common.

[MatsP]

There are all sorts of reasons why a cory may swim along the glass. Looking for algae as a food is certainly NOT one of those reasons.

The lack of interest in food is possibly a cause for concern - corys should be hungry most of the time, if they are healthy.

Unfortunately, without more information, it's hard to determine what could be the problem.

Perhaps answering these questions would get us into a position to provide a better help:
1. How long has the tank been set up.
2. How long have you had these cories, and what was the latest addition of fish to the tank, and when was that?
3. What are the test results for Nitrate, Nitrite and Ammonia? [If you don't have a test-kit, take a water sample to your LFS and ask them to test it - some shops charge a small fee, but it's less than the cost of the three tests].
4. What is the pH of your tank water?
--
Mats

[Corylover]

Hummm... makes me wonder Andy. I have seem her and her counterpart is an odd position. But I just counted it out as them hanging out and shoaling. I thought that swartz's corys didn't spawn. What do they're eggs look like, and how small are they. I have'nt seen any evidence of eggs but her counterpart seem to be munching behind her as she was cleaning a new spot this morning, he could be just eating some pellets .I just fed them. But none fell in that area I think.

[Corylover]

Ok matz, I check out my tank, and ready to answer some of your questions.

1. My tank has been established for 10 years.

2. I have had my swartzs cories for 1 year, I have not added any new additions of fish in my tank.

3. As for the ammonia and nitrite (I have to get a new kit the last strip got ruined so I'll answer that later)

4. The PH is normally around 6.8-7.2 but I will get a more accurate report when I get the new kit later today.

I hope this helps a little, I 'm concerned about her cause she's one of the greedest of the 2 cories, I have been feeding her the same ol food for serveral months maybe she wants a change maybe.

[MatsP]

Eggs would be about 1-2mm in diameter (like a big grain of sand), not quite translucent, some off-white colour. Most corys place their eggs on glass or under plant leaves. Almost all cories can be spawned in captivity, and C. scwartzi, I don't believe is a difficult one.

It is always a good idea to use different types of foods.

--
Mats

[DutchFry]

i'm not very sure, so please correct me if i'm wrong, but i believe a large water change could also be a reason for Corydoras species to swim along the glass.

the change in water quality could trigger instinct to migrate upstream (in the wild, of course) to their breeding grounds. maybe this is the case?

[MatsP]

i'm not very sure, so please correct me if i'm wrong, but i believe a large water change could also be a reason for Corydoras species to swim along the glass.

the change in water quality could trigger instinct to migrate upstream (in the wild, of course) to their breeding grounds. maybe this is the case?

Corys, as far as I know, do not migrate to spawn (or migrate in any other sense - they may of course swim randomly up and down the part of river they call home, just like they will swim from one end of the tank to another.

Of course if the water quality is bad or such, then they may try to "get out".

--
Mats

[Corylover]

Ok matz I've got the kit and so far everything seems normal.

Nitrate -20ppm
Nitrite-0ppm
Hardness-75(GH)ppm
Alkalinity- 180(kh)ppm
and PH -7.0

And No nh3 (ammonia) is present in the tank, and no eggs neither, unless they ate them.

Thanks for all your help in advance.

[jar]

This sort of behavior is normal behavior for corydoras. When the water quality is excellent, they will sometimes do that. Most of my cories will do this all day every day, for days in a row sometimes. Especially when there is a large group (ie more than 6) however my trilineatus do this and there are only 3 of them.

[Corylover]

Jar I think you're right I did a little 10% water change today cause I did'nt like the Nitrate levels in their tank. Well the next thing I know was as soon as they felt I was done. Lo and behold she started dancing on the glass, along with her signifacant other. And she eating again too.

The water quality is:
Nitrate 10-15ppm
Nitrite 0ppm
Alkalinity 180
Ph 6.8