"Also our dolphin wants a beautiful name! "How about
Delphina? -means "of Delphi", an ancient Greek city whose name is rooted in Greek δελφις (delphis), meaning "dolphin" ,which makes it a nicely circular name derivation!!
If it is a male dolphin, it could be Delphinus. If an Italian dolphin, maybe Delfina. If Irish, Deilf (meaning 'dolphin', strangely enough!) I vote for Deilf, but then I would...
Thanks for the fun activity,
Vic