Skip to main content
Home Northeast General Fishing & The Outdoors

21 Fathom

I have heard people in NE Florida reference 21 Fathom for bottom fishing and am looking for some clarity.  Is 21 fathom a specific fishing spot or a depth that is good to fish at?  


  • kayjay90kayjay90 Posts: 67 Deckhand
    Good depth to fish. If you don’t have any spots marked around that depth try trolling for a half day while keeping an eye out for good bottom and mark it.
  • StonehengeStonehenge Posts: 256 Deckhand
    OK, thank you for confirming.  I had always wondered. 

    I typically start trolling at a public numbers spot and find new spots from there.  They are always in close proximity.  However, I haven't tried trolling from a random location based on depth.  I would imagine this is when you begin to find really good spots.  
  • kayjay90kayjay90 Posts: 67 Deckhand
    Trolling around the 21fathom mark usually isn’t as productive as going out to the ledge but u might pick up on some scattered weeds and pick a tuna or mahi off certain times of the year. But if your looking to get into some bigger trigs and grouper it’s a good place to start IMO. Cheers!
  • elpollolocoelpolloloco Posts: 310 Deckhand
    21 fathom refers to depth or 120 ft, fathom is 6 feet. Our bottom here from is 80 to 100 foot from 15-35 miles out. When you get out to 35+ plus it drops to 21 fathoms. Then as you get out further you hit 23 fathoms.  23 bottom is full of ledges to fish as well. Another few miles past there you hit the "ledge" where it goes from 160-180 sharply? Something like that then it drops off after that to 500-600+ ft. 
    That is basically it. It refers to the bottom and how it drops off. 
  • StonehengeStonehenge Posts: 256 Deckhand
    Thank you all for the feedback!

  • Family TraditionFamily Tradition Posts: 101 Deckhand
    Stone you're right on about trolling in a general depth and finding bottom. When I started offshore fishing that's how I found all my spots. Started trolling for kings and learned nearshore waters then started trolling for dolphin, wahoo and tuna and learned deeper waters. If slow trolling you have a decent idea of what you're going over right away but if you're high speeding and mark anything on the bottom it's worth marking then going back over while bottom fishing. Guaranteed you'll find tons of productive bottom if you keep your eyes on the bottom machine. 
Sign In or Register to comment.
Magazine Cover

GET THE MAGAZINE Subscribe & Save

Digital Now Included!


Give a Gift   |   Subscriber Services

Preview This Month's Issue

Buy Digital Single Issues

Don't miss an issue.
Buy single digital issue for your phone or tablet.

Buy Single Digital Issue on the Florida Sportsman App

Other Magazines

See All Other Magazines

Special Interest Magazines

See All Special Interest Magazines

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Get the top Florida Sportsman stories delivered right to your inbox.


Phone Icon

Get Digital Access.

All Florida Sportsman subscribers now have digital access to their magazine content. This means you have the option to read your magazine on most popular phones and tablets.

To get started, click the link below to visit and learn how to access your digital magazine.

Get Digital Access

Not a Subscriber?
Subscribe Now