mikrogeophagus ramirezi. temperature 27C minimum. hardness 0-120ppm. pH less than 7.
for a group of 5, a tank no smaller than 36"x12" substrate area (height is mostly unimportant). they prefer a fine substrate (sand) which they will sift through their gills, but will do fine in any substrate really
what's the blurred fish in the first picture behind the ram, a zebra danio?