I have a tank with convicts and a couple other cechlids. Recently my biggest covict is living in a big hole in the gravel under rocks. I did not see her? him? dig it, but it is the most teritorial fish and has started spending alot time in there. I am not sure of the sex, but it changes colors and the tip its fins have an orangeish to yellowish color only at the very tips. So what do you think of this? Pregnant??