Roscoe is an adult Oscar, who in the past few days is swimming with his mouth open a bit. He (an assumption) isn't eating, where he's always been a good eater. He isn't "gasping" for air, but doesn't go down to the bottom of the tank much now, where before he would. He just doesn't look good, or normal. What could be his problem?

I have 3 Bala sharks, 2 tinfoil barbs, 2 plecos, 2 African cichlids (4") & another Oscar in a 210 gallon tank. Water quality checks out fine.

how old and how big is Roscoe? and the other oscar?

i had an experience with my oscars floating around
and not eating. then later on started to bulldoze the
substrate, attacked anyone that comes near to her
territory.

Roscoe & Boscoe both are about a year & a half old, both are 12" to 13" long. They have never fought, even though we bought them 2 weeks apart. Boscoe doesn't seem to leave Roscoe for very long, so it's hanging around at the top too, but it will eat.

thanks for the info... i will not question your water
parameter anymore. do you have substrate? if none, pls
put some slate or slab rock in your tank. you have a
matured oscar who is about to spawned. there is big possibilty
that the one who refuses to eat is the female while the one who
is still taking foods is the male. eventually, both will refuse to
eat.

watch out for their lip locking and shrugging.

Oh my.

No, we don't have substrate, but we will get a slab of rock to put in there.

If they do breed, what are the chances of having babies live? My husband thinks if that happens, he wants to keep one.

ha ha ha... no chance with the tankmates you have there

Oh good. I don't need the headache of trying to keep babies. If I'm reading correctly, it looks like they will appear to be fighting, so I shouldn't worry about it, just keep the tank clean. Which is what I will do.

Thank you for your help.

Karen wrote:
yes, you shouldn't, unless they turn out
to be both males where lip locking may result in injury.

the best for you and your fishes.

no problem.... we are happy of being able to help other habbyist.

Ooooh babies!! Think the tankmates will just see eggs as lunch tho.....

That's what I thought, especially with the cichlids, but I told my husband I would check.

please do give us update for any development.
i might be wrong but that is how i see your concern.

x2...........