Oscar suddenly passed

duanes

MFK Moderators
Staff member
Moderator
MFK Member
Jun 7, 2007
21,052
26,419
2,910
Isla Taboga Panama via Milwaukee
My impression is that the tank was "not" properly cycled and the oscar(s) were poisoned by their own ammonia (waste products, such as urine). Two weeks sound like just enough time for the water in a 125 to become a toxic soup.
It usually takes 6-8 weeks to cycle a tank, before it is ready fish such as oscars.
 
  • Like
Reactions: Mdoka and tlindsey

esoxlucius

Balaclava Bot Butcher
MFK Member
Dec 30, 2015
3,690
13,743
194
UK
That protrusion from its vent looks like a prolapse. This can happen through passing eggs or infection. I'm guessing your Oscar may have picked up something from your feeder fish.

That water looks awful milky too, sign of an uncycled tank. As previously mentioned, this "time out" period you are giving yourself needs to be spent swatting up on the basics of fish keeping. The most important area by far is understanding the nitrogen cycle. Failure to get your head around the basics will lead to many more painful experiences such as this one. Good luck, and don't give up, it's part of the learning curve.
 
zoomed.com
hikariusa.com
aqaimports.com
Store