i have a reverse trio of the yellow tail acei with rusties, labs, and white tops for over a year and a half. all 4 species have bred for me and have never noticed any of the males trying to cross breed. The males don't seem too interested in mating with the females of the other species. My female acei has held 4 times and have stripped her twice. She usually has over 20+ fry. They are slow growers, usually dark with some striping when tiny. You will notice some yellow on top when close to 1/2". The female and male adults are over 5".
I have a breeding trio of Acei. The fro aren't recognizable early on. They are small compared to my yellow lab fry when I strip them. You'll notice the yello on the fins somewhere around 1/2" in my experience. heir bodies darken up before they fade into the recognizable blue/violet color at about 3/4". They grow a lot slower than my lab fry.
I don't know ho big yours are, but if they are 1" or more you should be able to tell that they are Acei.
I can't speak for others, but I haven't read of any crossbreeding problems with any of the species you listed. I have kept them with yellow labs (and giant Demasoni) and male peacocks for an extended period of time and had no cross breeding issues.
Has anyone ever had Pseudotropheus acei have fry before? If so do they come out looking a liltle like fry from a peacock or are they colored from the start. The reason im not sure is I have a young pair and it is hard to tell if they are both females or a m&f pair. They are in a tank with yellow labs, demasoni, and some peacocks I picked up. Can Pseudotropheus acei crossbreed with any of these? Thanks agian for the help guys.