I have several (2 or 3) clown loaches with large black dot between 2nd and 3rd bar - is this just random variation or signal a different catch location (i have 13 in a 550):
I've seen Clowns with similar markings mixed in with more standard looking Clowns at my LFS.
The unusual marking is probably just a genetic variation, not a color morph due to geographic, environmental location.
I don't disagree but so much as turning my head will have them scatter. If at a later time i can talk them into sitting still i'll go for a better photo. Part of the problem is the glass on 550 is quite thick so i have to get relatively close; in a smaller aquarium id photo from further away and zoom in.