Dwarf Puffers

I'm assumine they meant livebear to be livebearer, a fish that keeps its eggs interally until they hatch therefore giving birth to live fry rather than just laying eggs. Usually thought of being the easiest fish to breed in captivity, recomended for beginners. most of them are also good community fish (with swordtails being very iffy)
 
if you are willing to set up another little tank, you might want to ask your LFS to special order a bunch of ghost shrimp for you. keep them in their own tank so they won't all get eaten.
 
Some dwarf puffers will not bother live ghost shrimp, or Amano shimp, or even red-nose red-tailed or red cherry shrimp. My DPs have co-existed well with all of those shrimp. Others consider any shrimp as food.
 
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