Corydoras odd behavior

Need number's for water parameter's not opinion's/statement's such as fine,normal,good,acceptable,etc
Also help to know how long the tank has been running with fishes,filtration,water change schedule,what water conditioner.
Is/are the fishes new fishes?
Might take a week or more for fishes to adapt to new tank assuming water suit's them.

So, in a sense, hovering?

Hard to say without seeing his behavior, whether he is fine or sick.

But I had a similar instance, where one of my C. schultzei 'Black' did this (hovering midwater) for a couple weeks, then started swimming laps around the perimeter of the tank all by himself for a couple weeks (probably won't happen to yours). Then after that he behaved like typical Corys and hung out with the group again. Mine didn't show any signs of illness/stress, so in my case, he was fine. Guess it's just individual personalities?

Well ,can rule out water chemistry being off or poor maint/diet appears to me.
Those were/are easy clues to help identify or eliminate possible contributer to odd fish behaivor ,especially if suddenly.(usually more than one fish affected)
No new fishes added lately, helps eliminate possible pathogen's introduced with same in my mind.

WaterLife said:

So, in a sense, hovering?

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Essentially yes. The canister outflow is directed towards the front of the glass and he may be hitting some waves but nothing like air-bubble riding or surfing directly in front of the outflow. He hovers in one spot, this doesn't change when feeding. I haven't seen him eat but he isn't always there, just way more often and his behavior has changed drastically. I did startle him but he swam about a foot in the other direction and then came right back. Very odd. His color seems a little paler than the other corys but I contribute that to the shaded areas where the other fish were hanging out and the fact that the solo cory is directly under the lights. No stress markers or indication of damage to the fish in any way. I shall do my best to get a video and link it, but no promises.

Easiest way to post a video is to upload it to youtube.

sdwindansea said:

Easiest way to post a video is to upload it to youtube.

Click to expand...

Okay, I don't have an account. I'll give it a shot

First photo of the fish looks like fish is rather skinny.
Do other's look like this?
AngelsPlus.com medicated food's for possible parasites might be consideration.