Thanks David, I was thinking cichlids would be of the smaller variety like Convict, Firemouth, Blue Acara, T bar, Salvini. All would be one sex to avoid breeding and therefore some of the aggression.
I don't think the tank is quite big enough for Geo or Juru.
The more I think about it the more I would like to go for smaller fish Dwarf Cichlids, tetras, cory, and small pleco.
That was one of the main questions I had was how to add tannins, but the tea idea sounds like an easy alternative. I am Auckland and my tap water is normally 7-8ph
I will definitely be using dried leaves in the tank, are oak the best option?
Michael.