Is this normal behaviour?

[Aronsaquarium]

I got my flagfin Angelfish a couple weeks ago.
In the beginning he was swimming like this into the current/Glass a lot of the day.
I feel like that was stress as it got accustomed.
Now he seems to graze around during the day time, but I think it’s more prominent when the tank lights go off that he’s swimming into the glass (current is there too) for like 1-2 hours until the house lights go out and he goes to sleep.
Poor guy looks stressed when he does this, but is he just seeing his reflection from the side panel and going at himself?
Is this normal behaviour?

Other than that, he seems totally fine most of the day.

(He’s gone through Prazi treatments in this tank, and is also in Coppersafe 2.42ppm)

Thanks!

 

[Gumbies R Us]

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