I've had trouble finding any real quotes on their growth other than that they slow down around 6"-7". They are omnivorous, need a good amount of vegetation in their diet, are very healthy eaters (i.e., pigs) so if you want full growth looks for multiple daily feedings. Like most fish, being in a large tank with good parameters and lots of swimming room will be important. Also, you'll want at least 5 to 6, since they shoal. Fewer and I've heard the dominant male will intimidate others to eat less. Other than the fact that they do get big and like to shoal, they are really nice fish, and the coloring and size (when full grown) is quite nice.