Nice tank! I always liked how frogbit floats around ... they look so cute! :P
I would suggest against tossing in a few RCS in there. Ghosties are territorial and will attack them. I would also keep an eye on your ghosties in case one or two turn out to be macrobrachium shrimp which will
nip at Zippy's fins
Macrobrachium shrimp are often mistaken for ghosties at the LFS when they're young. They can grow up to 4 inches!