i would NOT recomand a female.. a 55 is only big enough for a male alone with no other cichlids ( yes you can add danios-giant danios tiger barbs or whatever of them species as dithers ) BUT NO OTHER CICHLID. heck i have a female im growing out in my 75 and after seeing how big males get i wont even put a male in my 75, to me thats to small. males get to about a foot long female top out at 8 or 9 inches. again these are MY opinions and what i have learned through the years of keeping cichlids.