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How big are each cichlid and how big is the tank?
The jag doesn’t look bigger than 2 inches or so; the convicts would have to be a comparable size for this to work out.
Actually...you said the convicts are in a 75-gallon, right? How many convicts? It could work if it's only one or two and there are plenty of hiding places. But there would have to be a lot of hiding places.