Hi there,
The name translates as '2 stripe' apistogramma. There are quite a large number of colour variants (blues, oranges etc), so it would be worthwhile asking which variety and where they came from (wild caught or tank bred).
Size wise, males should get to about 9cm TL and females to about 6cm TL. They will prefer soft, acidic water (certainly if you want them to breed). My breeding pairs have a floor space of 18"x18" and I would recommend that as the minimum (or equivalent) for these guys.
As with all Aistogramma, peaceful (ish!!) but when they start to breed the female will vigourously defend her territory.
Some of mine
Apisogramma bitaeniata 'Fear'
Regards
Andrew