on a boat that draws 7-9 with a 76 ft mast
but live in Miami
and we have been in and out Biscayne Channel a dozen times in the big boat and 100 times in boats up to 6 ft draft
Biscayne Channel has a couple of shallow areas and we have bounced our keel
at least twice. It is untenable in any kind of seas perhaps over 4 ft. There is a shallow area between markers 4 and 6 and we then turn to starboard just before 8 and aim just to the south of the tip of Key Biscayne once inside the Key the deep water
is on the land side. At low tide you might bounce the keel
so at low tide we go into the Bay all the way through the Biscayne Channel and then approach "No Name" from the inside of the Bay. If you get 3 ft out of the Channel you are aground especially near the houses in Stiltsville, be very careful between markers 16, 18, and 20 they curve to port and at night it is very easy to be seduced by the light on 20 and go aground.
The best anchorage is outside No Name about 200 yds from the entrance in about 12 ft...no mosquitoes but you have to be out of the migration route
of the local power boats.
We always renew our SeaTow, their boats are closer than Boat US, before we enter the Bay and if possible time things to half tide rising. You can get into Dinner Key Marina through their main channel but we ran aground before we got to the outer docks...again half tide rising.
We run it at night but you have to pay attention and I have seen up to three boats aground at night. If you want to play safe go into the Bay and then approach NO Name from the inside.