I am late to this discussion but from the standpoint of Florida law, here is the nut. I am just going to address the law, not the wisdom of the OP challenging the suspects outside the home.
The "castle doctrine", even though the term is not in the law, does not apply here. If someone is breaking into your dwelling or occupied vehicle, you are presumed under the law to be in fear of death or great bodily harm, and that the person breaking in is doing so with the intent to commit a violent crime. You are also justified in using non-lethal force to remove trespassers and in defense of your property.
In Florida you are justified in using deadly force, or threatening to use deadly force, to defend yourself, or others, from the imminent threat of death or great bodily harm. Additionally, you are justified in using or threatening to use deadly force to stop the imminent commission of a forcible felony. Burglary is one of the enumerated forcible felonies. In Florida you have the right to stand your ground and do not have to retreat before using force. Of course all use of force cases are viewed through the reasonable man standard.
In the OP's scenario, the person committing the burglary approaching the homeowner with a pry bar when challenged would place a reasonable person in fear of death or great bodily harm. Secondly, the fact that they were in the process of committing a forcible felony (burglary) may also provide justification for the use of deadly force. You cannot use deadly force to stop a property crime alone, but burglary is listed in the statute. The justification for threatening to use deadly force (firing shots into the ground) is the same as for actually using deadly force against the person. In other words, if you can shoot them, you can fire warning shots. In Florida you are also immune from prosecution or lawsuit if your use of force is justified under chapter 776.
Florida law also specifically allows firing shots in a residential area when it becomes necessary for self defense.
So based upon the information I have from OP's post, he was legally justified and not subject to any legal action. Just because you could, does not mean you should, which is a judgment call.