My first cichlid pair!

Hello All,

I'm planning to get my first cichlid pair!!!
My dream cichlid would be like:
- not too big!
- interesting spawning behaviour (like most cichlids!)
- low agression (like very few cichlids)
- be able to catch/eat livebearer fry (see below)

I've narowed my choices to: Ramirezi, Kribensis and Neolamprologus
brichardi; AFAIK (and I know nothing about cichlids), the main problems
with those 3 options a
- my water is too alkaline for the Ramirezi;
- Brichardis are difficult to sex (I could end up with MM or FF);
- none are very likely to eat the livebearer fry;

What do you think?
Any advice you can give me?
Any pitfall I should be aware of?
Any other option?

the tank:
- 30g
- plywood
- open top
- air driven RUGF

furnitu
- mildly planted
- 2 pieces of driftwood
- 2 half coconut shells

the water:
- PH=7.3 GH=? KH=?
- NH3=0 NO2=0 NO3=?
- Temp=26C-27C (79F)

current fish:
- 4 adult otocinclus
- 4 juvenile SAEs
- 3 (1M/2F) local molly-like livebearer (Poecilia Butleri)

TIA!

--
Otavio Exel /\oo/\