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Sri Lanka Fishing Report

How to weigh GT’s Fishing Report

How to weigh GT’s Fishing Report Some people talk about their captures of GT’S in either weight or for some its all about about length.

Unfortunately many people over estimate the size of GT’S, which is perfectly understandable for as we all know far to well after a long hard fight that GT’S are famous for the fish will seem larger than it actually is.

But how can you find out the true size and measure of your prize? Well with a little help from our friends in the Andaman Islands there is a simple method which is also very quick to do, so you can get the fish returned to the water as soon as possible.

All you need is a simple tape measure, pen and paper.

  • First measure the length from Centre of lower Jaw to fork of tail in centimetres (cm.)
  • Second measure the girth just behind pectoral fin in centimetres (cm.)

Below there are two images showing you the measurements being taken.

Once you have the measurements record them on pen and paper so when you return back from fishing you can calculate the actual weight.

Once back on dry land just use the simple formula below that can be used to calculate weight which has been proven time and time again to be accurate to +/- 5%

Length x Girth x Girth x 2.74/100000 (fish to 30kg)

Length x Girth x Girth x 2.70/100000 (fish to 40kg)

Length x Girth x Girth x 2.60/100000 (fish to 50kg)

Note: all measurements in cm

A lot of people are surprised at the actual weights of their fish, but it is our opinion that the real weight of the fish makes landing that monster that much more of a valuable and prized catch.

To view all our slat water destinations Click Here

Kind Regards

Peter Collingsworth


  1. Peter Collingsworth Sportquest

    I just love catching these fish, especially on the fly. Who wants to come catch some with me 🙂

    1. Paul Stevens Sportquest

      Make sure you hold me a space

  2. Arnout Terlouw

    On the first picture I see the tape measure untill the end of the tail, nut until the fork of the tail… is that correct?

    1. Peter Collingsworth Sportquest

      Hi Arnout

      The tape measure is laid out the length of the fish but you only take the reading from the fork of the tail.

      In this picture the tape was just roughly laid out.

      Thanks for commenting

    2. robert

      hi peter i would love to catch a GT could u give me more info about trip & costs

      1. Peter Collingsworth Sportquest

        Hi Robert

        It would be a pleasure to talk to you and give you details about fishing for GT’s. We have lots of different places that you can target these fish. Please e-mail us on and we can then reply to you in private.

        Regards Peter

  3. Steve Hess

    Using the suggested formula, is the estimated weight in pounds or kilograms?

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