It looks Ps. Polit and more likely a female. Male is pale blue with dark face when sexually active. Just a little doubt if it's actually a Polit 'coz the shape of mouth. I'd say it is if size is 2"-3" for a year old one.

looks like a african blockhead, it will take a very long time for them to grow, but hard to say cant see the face very good but looking at the way it is tells me blockhead, does it swim with tail down and stays mostly on bottom?

it has a blueish green tint to it . very small

Variabilichromis moori(formerly lamprologus moori)