J.G.
Ahahahaha yeah, it is hit or miss whether a float trip is family friendly. Pretty much float trips are about getting drunk and having sex in less than appropriate places.
I could list everywhere I have floated because they are nice places to float but if you are looking for somewhere that is "family friendly" only luck will place you there when kids aren't floating.
I just take my kids and figure it is a good learning experience beyond the floating. :-/