When would a bifa start to exhibit the top stripe (actually more like a long blotch)? I have 4 that are 3 - 4.5 inches and I only see the one lateral line stripe so far.
I have 1 and I will say he has had his since i got him. I picked him up when he was about 2". However his line you're referring to was weak like. It was not a solid line at all. More peppered like.
He is now about 6" in length and the line is more pronounced. It appears to be blotchy like but way easier to see.