What are you feeding your mollys? If you are just feeding crushed flakes then yes they will grow extremely slow. Breeders feed newly hatched brine shrimp.....you should be able to buy eggs at your pet store. If available to you, micro worms, grindal worms and white worms....usually from live cultures that you might be able to get from a member of an aquarium society. Once big enough frozen blood worms and other foods can be introduced. These foods will make them grow fairly quickly.

Now having said that.....sometimes fry don't grow for a reason.....could be water quality...or could be deformities that arn't visible because they are really small.

Hope this helps.
Sierra

Its either from not feeding them enough or feeding them foods they cannot utilise, change up there diet some.

Also: whats the temp in the tank like, if its below 75 or above 85 it might slow down growth aswell.

Omg 16 years well if u can reply me now can u tell me what happened ahead as i have same issues as