Top Dwelling Fish?

[TekFish]

Can anyone recommend me a top dwelling fish please?
Criteria:
Has to be shoaling,
Cannot be aggressive,
Cannot be a Hatchetfish,
Has to be remotely colourful.

Any ideas?

TekFish

 

[N0body Of The Goat]

If no small fish, a hareem of Golden Wonder Killifish, females do school together while the male tries to drive single females to spawning sites.

Alternatively, Beckford Pencilfish, my six behave much more socially in my 48x12x15 than they did in my 620T.