cichlids and bala sharks?
Got 1 in my 130G with large centrals and South Am, he gets no trouble. He's quite big himself though. If you read up on them, most suggest putting them in groups ideally. Mine is happy enough, active, healthy and eats well. Not sure how you would do with Mbuna as a comparison.
I think I'd agree that if you want it for the long term you would need a tank of 125g as they can get seriously big.
And yes, Mbuna need harder water. I have a neutral 7.5 Ph in my tank.
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