We just brought home a new Oscar today and while it was swimming around fine and fairly active. But once we turned off the lights it seems, he is now floating around near the top of the tank. He's not dead, and he's not really gasping for air, just floating around at the top and freaking us out. Is this normal? I've only read about then laying on the bottom of the tank. Any ideas? Maybe we'll just see if he's still around in the morning. Any help or comments would be appreciated. Thanks!

can it swim to the bottom and stay there? or does it need to keep swimming down to stay at the bottom? does it have any buoyancy problems. did you acclimatise the water from bag to tank slowly?

also welcome to ofl, just noticed its your first post )

he can swim down to the bottom and spent a good deal of time down there earlier today. we brought him home around 1 this afternoon and it's now 3 am. it's really just after we turned of the lights for the night that he has decided to just hang out up top. it almost looks like he's sleeping. but at the top of the tank? seems wrong. and yes, we did acclimate him to the tank slowly when we got him.

I think its going to be ok. most fish will go to the bottom and hide, have you got any hiding places? but depending on the fish personality it may just feel at home. do you have other fish in the tank?

also did you cycle the tank before you put your oscar in? what sort of set up have you got. filter? tank temp? do you have a test kit to test your water?

Welcome to our community forum

Exactly how long does this behaviour start after turning out the lights? What you have got to remember is that fish do actually sleep, sometimes they huddled together in a corner, other times they may just float around the tank motionless. Fish will normally go to sleep fairly quickly after the tank is in darkness. Whether this is what you are experiencing I can't really say. It could well be that the fish is behaving like that because they are not nocturnal fish and maybe he is remaining motionless so he doesn't attract attention to himself. Just a theory.

ive come out at nite to check the tank and i find my O just sittin on the bottom sorta leaning against the glass, almost like he is sleeping, turn the lights on and hes like AHHHH and swims round frantically, maybe he is "sleeping"

Mine do sleep at night and since i got nightlights i can see that they're floating close to the surface.
that is, with their heads upwards and their tail down in a 45o angle.
they seem to stay "straight" though.
I mean the top fin will be pointing upwards and they maintain equilibrium, even in the dark.
Goldfish and carp will lose that equilibrium in the dark, opposite to oscars and will also float in a sideways angle.
If he's not floating sideways, i think he may be sleeping.

And welcome ot the forum, btw.
Keep us posted what happens in the morning when lights are back on.

Thanks everyone for the feedback. he's alive! we're fairly new to fishkeeping and my husband became attached to this oscar the moment we brought him home, so having him float so close to the top was alarming. but, i do think he was just sleeping.

thanks again!