Tarpon Basin is crossed by the FL Keys Inside Route, just south of Blackwater Sound and Dusenberry Creek. There are at least 3 good spots to drop the hook here, and creative skippers will find more.
A couple of years ago, Monroe County established a pump-out boat serving vessels anchored in Tarpon Basin, and the locals chipped in with a dinghy dock on the nearby shoreline (see /?p=24226).
Sounds like Captain Mary found the pump-out service very polite and most useful!

We used the free pump out boat at Tarpon Basin by the government center today. We told the guy that we had planned on pumping out at Gilberts Marina. He said they don’t have a pumpout, but he will go up there in his boat. I called Gilberts and verified that, and they said they don’t have a pumpout, but they have a phone number that you call for someone to come there and pumpout. The phone number for the Monroe County pumpout boat is 305-747-2388.
I might add the Monroe County pumpout is FREE. The guy was very nice and said he usually works M-TH, but they try to be accommodating. I asked him how far he will go and he said he goes up to Gilberts Marina and down to Tavernier. He also said that eventually all of the Keys will have pumpout boats.
Mary Dixon

Click Here To View the Cruisers’ Net’s Florida Keys Anchorage Directory Listing For the Tarpon Basin Northern Anchorage

Click Here To View the Cruisers’ Net’s Florida Keys Anchorage Directory Listing For the Tarpon Basin Southern Anchorage

Click Here To View the Cruisers’ Net’s Florida Keys Anchorage Directory Listing For the Tarpon Basin Interior Anchorage

Click Here To Open A Chart View Window, Zoomed To the Location of the Tarpon Basin Anchorages