Just offshore of the Keys the waters of the Gulf Stream flow like a river to the Northeast. Its position varies, sometimes it just off the reef and sometimes it might be 20 miles offshore. Most of the time you will find your dolphin somewhere in the current. Weedlines are usually productive in offshore fishing too as floating objects that have been in the water a while. There are a few underwater mountains called Humps offshore from about 12 to 18 miles and they will hold tuna but it isn't rare to find billfish, wahoo and dolphin there some days. You will need to book a 3/4 or full day to go offshore. On these trip you will appreciate the lack of diesel fumes!