Pellets I think are the least messy food you can give(if they fit in their mouths)
I start the little guys off on crushed or broken flakes, but as soon as it fits, switch to floatting pellets.
Like cole said, it is probebly helping them eat it. They may be too stiff with not enough water soaked in yet.
With the pellets, they take a few of them and swim away holding them in their mouthes until the can digest them. Usually less mess that the flakes.
Tetra also has a thicker, less of a mess flake, which my bro-in-law uses.