Without knowing exactly what's going on in your tank, a few suggestions:
Swordtails and Glofish can get big enough to eat even full-grown ghost shrimp, and any fish that can eat a shrimp will love to do so.
Ghost shrimp are generally sold as feeders, and like all feeders are likely to be unhealthy. If any were white as opposed to clear in any part of their bodies when you got them, they were on their way out.
Unless your tank is completely bare-bottomed, it's not reasonable to assume you can see all shrimp that are present. I can probably count 25 shrimp in my 30-gallon tank at any time, but I'm sure there are over a hundred in there.
They also sometimes come up in the gravel vac if you're not careful.
As to breeding, I don't know what you have exactly, so the following assumes you have the southern ditch shrimp Palaemonetes paludosus, which is the species most commonly sold as "ghost shrimp." There is no chance of raising babies in that tank, because you just have too many fish that would love to eat them. The larvae are small and tasty, besides being weak swimmers that tend to float at the top of the water just like flake food. This behavior also makes them ill-suited for survival in a conventionally filtered aquarium, although they would probably make it with an undergravel or sponge filter, actually.
I've found that the best bet for larvae survival is to remove the berried female to an unfiltered quarantine tank or 5-gallon bucket. Ideally a lamp over this and some floating plants would provide food for the young. Driftwood or just a handful of dead leaves (brown ones from the ground, nothing that still has sap in it) will also provide a food source. If you do this, make sure the eggs are external to the female before you move her. The eggs develop internally and are visible for some time before they have been fertilized. Once they are release from the body they are ready to hatch and no longer require a male. At this stage they will be held tightly in the swimmerettes under the mother's tail, where you will see her constantly juggling and fanning them to provide water movement.
In theory there wouldn't be anything wrong with removing the female and a male to quarantine at the first sign of eggs, but I have no idea how to identify a male shrimp.
