I have Seven platy fry, or what I am guessing are Platy fry. They are around a month old. Because I wasn't aware of them until about three weeks ago I think their growth was a little stunted. Since they moved to the hospital tank they seem to be thriving and are now almost a half inch long. I have a grown male Guppy with them and he has not made a move to eat them. Is this big enough to reintroduce them to the big tank? I really need to move the hospital tank and cannot do so with them in it. How big should they be to move? The main tank is 55 gallons and has about 12 mid size live bearers. There are plants in the tank to allow them hiding and I'm nearly ready to put driftwood in as well.