Active Otocinclus and Panda Cory

[Clementi]

Hi Bros, I have done a 40% water change yesterday and noticed my Otos and Panda Cory seems to be hyperactive. I had 2 Otos for over a year and 2 new addition 2 weeks ago. Recently noticed the older Otos seems to be more active than before. Is this normal or sign of stress?

[Quixotic]

Most probably normal, assuming that there is nothing wrong with your water conditions.

Not many people are aware but Otocinclus are actually schooling fish, so the greater the number, the more you see them interact with each other, you may even see one chasing another across the tank.

[illumnae]

i've seen that happen in my 4 footer...very funny to watch

[Clementi]

Cool, good to know that. I could see the 4 of them swimming up and down which never happened before. I was worried but kind of nice to see them so active. My Panda was swimming in pairs too. I was worried the water change has impacted them. Thanks guys.

[CK Yeo]

My cories does that when they want to spawn. This is usually after a large cool water change. Maybe the weather contributed too.

ck

[Clementi]

My tank average temp around 30 degrees, after water change and windy condition temp drops to 28. Is might be the reason why the cories and otos were so active.

[aquanatix]

I do realise both otos and corys get more active when colder temperatures are present.Quixotic is right about them being schooling fishes though. Wait till you encounter otos with identity crisis! Mine often shoal with my 15 corydoras pgymaeus and 10 hastatus! A huge shoal of dwarf corys and 4 OTOS are really a sight to behold! Never fails to amuse me wheneva i stare at my tank!

[Freshman]

My tank average temp around 30 degrees, after water change and windy condition temp drops to 28. Is might be the reason why the cories and otos were so active.

30degC is too high for most corydoras. Too damn high for panda cory IMO.

I believe most cories are always active but will become hyper active when their breeding mood is being triggered.

If I remember correctly, the drop in water temperature caused by either large water change or heavy thunderstorm will trick them into believing that the rainy season is here and it is time to reproduce.

Last night my bronze cories are all dancing around in my 26degC water. (usually is 27 or 2 Expected to see some leftover eggs tonight after they laid and feasted on them.

[Clementi]

The current cool weather has kept my tank temp around 27.5-28. My panda cory is doing well, swimming in pairs but my 2 bronze cory died mysteriously. They seems ok, swimming and playing around but found one dead followed by another dead 1 week later.
I'll install fan soon to keep temp down. The cool windy months will be over soon.
Any pointers I should note to keep them. Mine is a community tank consist of mainly tetras and 6 harlequin rasboras. Heavily planted too.

[Freshman]

Hi Clementi,
Do you mind providing us with more info on your tank water parameters, behavior before death & appearance after death.
Some pictures of your cories and its setup will help also.
Also, is your filtration cycled? Personally I feel that 40% water change is too much and might cause stresses to the fish.

Heavily planted setup might not be very suitable also as corydoras could somehow get trapped somewhere inside. (My friend's corydoras got stucked under a piece of DW, Another guy's corydoras get entangled in his thick plants)
However, It is still possible to keep them but careful consideration has to be taken in plants & woods arrangement.

[Clementi]

Thanks Freshman, I'll try to take some pic of my tank and the remaining 2 cory. I'm left with 2 panda cory now. Still surviving, fingers crossed. I just did another 50% water changed on Sat and the casualty are cardinals. 9 dead out of 19. i think you are right to say, 40-50% water change is too stressful for the fishes.

[Clementi]

Tank 2 1/2 feet. Started the tank about a month ago. Added cory 2 weeks later. It is low tech tank, I dont measure kh or ph. Temp around 28C.

[corydora]

did you notice any darting, scraping against dw or substrate? corydoras are usually more susceptible to internal parasites because they lack scales. c. panda is also extra sensitive to water-quality compared to other corydoras so maybe it was the large wc that made the difference.