I used to keep both of those. They were both some of my all time favorites. They will go from 3" to 6' in about 3 months, so it won't take long to get that size. It still may be difficult to vent them at 6". I found both species to be quite docile by cichlid standards. The pearsi male would get pissed if something nipped his fin and bull rush the offender. Other than defend himself and some minor shoving at feeding time, I did not have aggression issues (both species were in separate 240 gallon tanks). Both species are awesome show specimens as adults. I wouldn't worry too much about getting a female, other than being a little smaller sized, and having a little smaller forehead, they look awesome too.