gregb

Have you had this tree in Florida the whole time you've had it? You mention that you shower the tree when you water it. The leaves look like they have bacterial leaf spot, which is water-borne (bacteria gets on leaves via water)

Try watering the roots of the tree and keep the water off the foliage. It has to be pretty humid in Orlando anyway and there should be little need to water the foliage. And if you're in doubt, take the tree to your County Extension Service. They have a master gardener there to diagnose plant diseases and the best of all--it's free. Your tax dollars pay for it. Look in the phone book under the county pages for the number. Do it as soon as you can. Another thing, I don't know about trident maples, but I don't think Japanese maples can be grown in Florida. Maybe you are trying to grow a species that doesn't do well in that climate. Let us know how it goes.