Adding shrimp with bettas is hit or miss.. My betta spent all day trying to kill my shrimp.
LOL...Yepeprs, know this one well, at this point.
My Oscar started making snacks of my original ghosties. So, I saved the ones I could and put them in with my girlfriend's bettas. She has a female and a male. The male leaves them alone, pretty much. The female, however, has eaten every last one she can find.
Bascially, remember that ghost shrimp are at the bottom of the food chain. Everything will will eat them.
Of course, I'm going to try my hand at breeding them, for my Oscar.
Also, they are really cool to watch.
When you put some food in the tank, and see them hang upside down while eating it...that's just fun right there. LOL