Legal Question in Civil Litigation in Florida

You can garnish bank accounts. You have to obtain a writ of garnishment and serve that on the bank. You don't need the complete number to do that. That said unless there is significant money in the account it may not be worth garnishing. There are costs for the garnishment. You have to deposit a fee for the garnishee and likely a clerk's fee for the issuance. You have to serve it by process server as well. the costs related to the garnishment are recoverable. Seek some legal advice, these are technical and difficult areas of law for lay people to handle on their own.