Mine seems to graze on the bio film that developed on the leaf litter.Oak leaves --- like just from Oak trees in the neighborhood?
Also, may I ask what you fed the fry as first foods?
I'm having trouble with my German Blue Rams -- I get the fry, but they perish. It almost seems that the BBS are too large --- or perhaps something else, like not using R/O water.
I normally feed crushed fake and boiled egg yolk crumbled up.Its a little messy but a good food for tiny mouths.