Corys ..gone shy !!

[jayg]

HI.. bit new to this !... and to corys..really love them and have four bronze.. 2male 2 female ..(I think !)... have a 4 ft planted tank , now 7 mths old .. small gravel substrate, plenty shade and bogwood.. temp 24 , ph 6.5-7.0, ammonia nitrate and nitrite ok.. phosphate gets to 2.0 after a week, change water every week (25%).. tank mates 6 lemon tetra, 8 cardinal tetra and 1 flying fox (siamensis ).. all get on ok. Fed on flake and frozen bloodworm.
Now the problem !!...The corys have been fine ..out all day..busy feeding, spawning ..very happy for 3months and suddenly for the last 3 weeks have gone totally nocturnal..very freaky and shy and won't come out from under bogwood if any one is around !!.. a total personality change..
I really can't work this change out.. as far as I know there has been no major chemical change .. they seem well when I do get a peak at them and other tank mates all behaving normally.. as far as I know there has not been any trauma or bullying...
Any ideas please as I really miss seeing them .. I know they can be nocturnal but would they totally change like this and is this typical behaviour for this cory or can it be seasonal ?

love to hear from any wise owl out there please !!!

[CoolTcat]

I'm not going to be much help as I have been hoping that someone else would answer this one.
I have had the same thing happen and I think what has initially triggered it for me is chasing them with a net for tank change or big cleanup. I could not believe how difficult they were to catch the first time I tried it. Has anyone any hints?
They seem to me to have quite good memories, (or bad perhaps from the point of veiw of the fish).
I have noticed that they do seem to snap out of it with a big water change. Maybe all is forgiven with the onset of the wet season.
Good luck with yours as it is such a pity not to see them.
Jan

[Taratron]

I'm having this problem myself with my brochis cats.

I posted a week or two ago about them not schooling, and now three of the four of them are, but they are dashing all over the tank when anyone approaches! The fourth member often scurries with them, but they are moving very fast, and I'm afraid they will hurt themselves!

Oddly enough, the elegant cories I added two days ago are calm and not running around maniacally.

Tank size is 29 gallons.