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I have a 20gal tank with four different type of cichlids, all males or so I thought. the other night I was watching them move the gravel around, because I spent hours making it flat for them. well as I am watching them I see a little movement in one of the caves in the rear of the tank while all four fish are feeding. I couldn't quite see what it was, but something was in there. when they all finished feeding I decided to move the cave and see what was in there. when I moved the cave I got the surprise of my live, what I thought was a piece of plant that was moving in the current was a little fish about half an inch long. now the question is where did it come from? nothing new has been added to the tank in 2 years and all the fish are male, verified by a cichlid enthusiast. i think the enthusiast was just guessing and i have no idea on who the female is in the tank but soon they will be moving in to a new 55gal because they are out growing this one. i will try to get pictures when i move them to their new home.