Why are some of our platy frys still itty bitty while some are like triple their size?

Question

They were from the same mother and born in generally the same day. Some don't look like they grew at all, except for the fact they're not still newborn-size.

Answer 1

The bigger ones, are either the dominant ones,and, or males. Males grow faster, and the dominant ones get the food faster. This is perfectly normal.

Answer 2

The bigger ones get to the food faster, thus they grow faster. Separate the larger frys while keeping all of them well fed, they smaller ones should be able to catch up in no time.

Answer 3

Fry grow at different rates. I would separate the larger ones and the smaller ones, so the smaller ones get enough food.