Do you still have large numbers of FHM in your pond? If your pond is still overflowing with FHM as is often the case for the first year after stocking bass, I am not sure tilapia would be a real big assistance. Tilapia like BG have spiny dorsal fins and are not going to focused on with a bunch of non spiny FHM swimming around. Until your FHM are extirpated by the bass in your pond, I don't see a real need for tilapia unless you are experiencing an FA problem or some other need besides added forage for your bass.

If you have the cash, you can always add them though...