I agree with extra cichlids thrown in the mix to dispearse the aggression.
This vid is a 1000g tank.(your pond would have a better footprint than this)As you can see it seems to work pretty well.The Umbee is the only one I would be unsure of.It is the sort of thing I am aiming for when I build my ply tank of 1140gal.Minus the RTC and replacing the silvers with a Jardini.
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