I am not clear on if they can empty a bank account totally in Florida if it is not an exempt kind of income.
Yes, they can.
They can also take the exempt amount. It's up to you to get it back by proving it was exempt.
They send a garnishment notice to where you bank, or where they think you might bank. Any money on deposit is handed over by the bank to satisfy the judgment. If the judgment is more than your account balance, the account will be emptied.
The only exceptions are for exempt Social Security direct deposit accounts, or accounts for which you have notified the bank exempt income is contained. Even then, banks have been known to ignore exempt amounts.
Don't keep money in the bank if you have a judgment against you.