As above really. Want to add a bit of colour but unsure as to whether they would start to get territorial. Got a few Discus in there, 4 cardinals, empire gudgeon, Leopard Gourami (African Bushfish), a Blue Line Goby and a Rainbowfish 
You do know the bushfish is likely to treat your Cardinals, Goby and possibly the Rainbowfish as "live lunch" eventually? Bought 3 of my 4 two years ago, the size of a 20p coin, now 10cm and will grow another 3 or 4cm.