They are gregarious rather than shoaling so REALLY appreciate company. If there isn't a group of them, 4+, then you will very rarely see them (even in a 10gal). That wouldn't be natural cause naturally they should feel safe and be very active.
Personally I wouldn't have them in a 10gal, not cause they can't grow to full size, and not cause the bioload with be too much.
Purely cause they are super active fish, they literally bounce off the edges of the tank and I don't feel they'd be 'comfortable' in a 10gal.
Edit: Just to add they aren't always super active, but I found mine had a good race around the tank for a few hours each day.
