Once mine get where they look big enough, I try crushed flakes to see if they eat it. Then I feed both for awhile, alternating flake with First Bites. Even my 8 week old mollies still like their First Bites. Plus, its designed for babies. I think it helps them grow just like puppy food. Is she alone in a tank? Must be hard not to over feed one baby. I would be nuts about water changes. Partial changes every other day or so depending on her tank. If she in a breeder, her extra will just fall through and the other fish will get it. She's pretty small to be a month old. What is she? Are you feeding her frequently? I feed my fry 5 or 6 times a day. You can practically feed fry every hour or two as long as you keep the quantitiy correct and the water clean. My 2 month old mollies are over 3/4 in long. I have 3 wk old guppies at nearly 1/2 in.