IANAL, but as I understand the law, a hung jury results in a mistrial with no verdict given on any of the charges.
Florida Criminal Code would dictate whether or not the State can file new charges and which charges are allowed under the law.
I would assume they could refile on 2nd degree murder and the lesser included charge of manslaughter.
I’m going to go against the majority here and say that if — IF — there’s a hung jury, FL will not retry.