You may want to try googling how to raise platties, to supplement the information you get here. What breeders feed them, how fast they grow under certain conditions... You get better result when you look up how to raise swordtail fry.
I have great success with microworms and decapped brine shrimp eggs. I highly recommend feeding that if you can!
Yes the reason I firmly advise against using ghost shrimp is because they are predatory to small fish such as fry. There are several forum members who have lost fry to ghost shrimp, and I myself have lost adult platties. I do not keep ghost shrimp at all anymore. Plus they are so annoying to breed, neocardinias are much more harmless and pretty and easier to breed
And I'm not sure why you think ghosties will tear up plants. ghost shrimp won't tear up plants, they are far too puny for that. Do you have shrimp that do that? They may not be ghost shrimp at all in that case.
The other responder is correct. My platties drop fry every 4 weeks like clockwork!