Danios Gone Mad!

[Naidisbo]

This morning I woke up to find my Danios completely out of their normal shoal, smashing into the sides of the tank, torpedoing themselves down into the substrate and just all around making a commotion!

The only thing that I know of that happened last night is that at some point the heater got unplugged, and the tank was freezing. Well, 68 degrees, but still too cold for the Tyretracks I have in it. However, they are fine and they don't seem to have anything wrong with them... It's just the Danios!

They calmed down now...
Was it just the change in temperature? Could they have been scared by something?
I'd figure if it was the water chemistry the fragile eels would be the ones showing signs of illness, not the hardy Danios.

 

[Byron]

I'm not going to guess, but it certainly could have been the temperature drop, or something else. But so others can offer suggestions, can you provide some data. Tank size, fish species and numbers, water parameters (GH, pH), tests for ammonia, nitrite, nitrate, and water change schedule (frequency and volume). All of these help us diagnose issues.

Fish being ectotherms, their physiology and metabolism is driven directly by temperature, so any sudden changes can cause severe stress and more, as can too cool or too warm a constant temperature.

Byron.

 

[Naidisbo]

Forgot to leave an update/delete this post last night... Figured out what happened pretty quickly.
Thank you anyway, though!
Looks like the eels are just finally going after larger food - Later that day I found half of a Danio in one of the logs.
Guess they had to have been trying to hunt them in the morning, caught one in the middle of the day.
Had to move the Danios to my mom's tank until the Tyretrack's new 30gl tank is finished cycling.

Really crowded in her tank though, debating if I should just move the Danios into the cycling tank to avoid stressing out the other fish, or leave them be so I don't stress /them/ out, or get them sick...