55G Cichlid Tank

I agree, we often have to keep 20+ in 55 gallons to keep them alive. The mbuna I have are about as aggressive as demasoni. Luckily we have massive filtration and the nitrates stay under control. Second the synodontis cats as well. I've always liked the cuckoo cats myself, just never had a tank big enough for them (my cichlids are at my work).
 
You could also do shell dwellers if you like. They would be a good option. Or! you could switch to Lake Tanganyika and do brichardis.
 
Shell dwellers are hard for me to come by, as none of the LFS carry them, and I don’t want to risk shipping in my weather up here. I had kribensis before and I love their colors and personality. I think I can get away with a trio in this size of a tank. I do like brichardis, but again have to have them shipped. I have bad luck to fish being shipped.
 
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