Hosty - If you truly mean "fry" by the technical fisheries definition then, no, you will not be able to separate bgill fry from minnow fry unless you use 12X to 20X magnification and know exactly what morphological features to look for.
Technically fry still have evidence of yolk material. When yolk and oil are absorbed and the young fish have fully developed mouth parts and begin feeding on external food items then they are technically called larva or larvae (pl). Fish larvae have two or three developmental stages depending on which taxonomic philosophy you use.

Once the larvae (abt 0.75"-1" long) develop a full compliment of fin rays, then they are called a juvenile and are usually recognizable "in the net" without magnification if you "know" your fish pretty well. Juvenile fish are also commonly called fingerlings.

I think you can stock your fingerling bass (2"-4") in May or early June. They will begin feeding on last year's young minnows right away.
Bluegill will for sure spawn in June - July and bass can then also eat minnows and small bgill for the remainder of 2005. Bgill will then be the backbone of your forage fishes. Minnows (fatheads) will be scarse or absent late next year (2006).

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