ive had my goldfish fry for about 2 months now...they are still rather small. when should i put them back in the parent tank ?(the largest in the tank is a 5 1/2 inch oranda, and the tank is 55 gal.) i dont want them to get eaten >.< thanks for any advice.

If your big fish have big enough mouths they may eat them. I would wait until they are bigger to be honest.

Don't put them in ye as they will definitely get eaten unless they get sucked into your filter first.
It will be a while before they can go in with their parents. My fry are now 3 and a half months old and are still narrower than my smallest fishes mouth. I reckon in a nother month I might be able to think about moving them.