sexing my albino ruby shark

[whatsmango]

hi there everyone, im a newbie to the site.
getting straight to the point, i have two ruby sharks, one black, one albino (and they get on fine). the black is definately a male, as his anal fin is more black than orange.
while looking on the net though, i could find no information as to the sexing of the albino species. it appears slightly plump and its anal fin appears to have a white tip.
could anyone please give me some help into determining its sex please? itll very quite appreciated!
thank you!

 

[Erik]

well females seem to be plumper

 

[whatsmango]

ive had a better look of it now, and i reckon its a male. he's got a sort of diamond shape on his body before his tail in a brighter white, and the black ruby is similar (in that he's got a darker black marking of the same).

thanks for the reply though!