Stocking 55G (and the coolness of kribs)

[Elariel]

When I first got my 55g in January I thought I would turn it into a Lake Mbuna cichlid tank but a friend of mine had given me a Krib and kuhli loach that was had been leaving in her 10g together due to being picked on in her bigger tank. She said that she rarely saw either.

The kuhli found a home in my 30g asian/south american community tank. He is now sticking his head out from his favorite hiding place at feeding time searching for shrimp pellets and occasionally comes out for a swim. He is so much fun to watch!

When I first got the Krib he had very little colour and his fines were deteriorating. Now he has a lovely red belly and his fines are always up. He bosses around the other cichlids in the tank! He has made me switch from wanting Mbuna to wanting  west africans!

So right now I have in a 55g (48x12x17):

4 Hemichromis guttatus (three spot jewel cichlids)
2 Hemichromis lifallili (red jewel cichlids)
1 Krib
1 BN Albino Pleco (Ancistrus sp.)
3 Australian Rainbowfish

I have been told that I really should have 6 rainbows. Would this be possible in my tank? Would it be possible to add a female krib as well?