Thanks guys. I'm begining to think the yellow Cryptoheros is something close to Nanoluteus also, although they look different from the Rio Rabalo strain I've bred in the past. I'm not familiar with any other strains of Nanoluteus to compare.
Thanks. The blockhead male Sajica runs the tank. I've tried to get to the bottom of Altoflavus vs. Nanoluteus over the years with no luck. Some circles seem to think they are the same species and Altoflavus is just the name used in Europe.