Hook Corrosion Rates in Salt Water

I was asked one day "what about all those fish thatGamakatsu Live Bait - Corrosion started after 4 days
get away and end up swimming around with a hook inThereafter up to day 10, apart from some continuing
their mouths ?"mild surface rust and furring on the Duratin hooks,
Well, undesirable as it is, it does happen and aboardeverything seemed to stabilise and nothing much
our Gamefishing vessels, we always use hooks madehappened.
from Duratin when using real baits, bait / lureOn day 10, the Maruto SS1920 Stainless Steel hook
combinations or in a lot of our wahoo and large marlinfinally showed some discolouration and then on day 12,
lures. Duratin, I explained, in contrast to Stainless Steel,some minor rust spots on the eye and shank.
corrodes rapidly in seawater so the hook quicklyOn day 14, all the hooks were tested with the 5lb
deteriorates and falls out or is ejected by the fish.weight and all passed with flying colours. There did not
It then occurred to me that I had never actually seen aappear to be any deterioration in strength in any of the
study of just how long it takes to corrode a hook tohooks.
the point where it is likely to drop out or be expelled byAfter 21 days the hooks were removed, lightly wiped
a fish so I conducted an amateur bench test:with a cloth, photographed and strength tested.
I selected a range of hooks we most commonly useAll hooks showed widespread corrosion except the
aboard our game boats. I included only one StainlessGamakatsu Live Bait and the Maruto Stainless Steel
Steel light gauge (Maruto SS1920) as a comparison tohooks which only showed slight corrosion on the hook
the Duratin hooks.barb and bend. The Duratin light gage SL12S was the
The following hooks were tested:most heavily corroded. A second SL12S that was
1. Mustad 7766D (Duratin) - 8/0, rigged baits and skirteddipped in salt water each day but suspended in air
lures for wahoocorroded far more heavily than the one suspended in
2. Gamakatsu SL12S Saltwater fly big game hooks -salt water - presumably because of the increased
10/0, Light tackle rigged baits for sailfishlevels of oxygen in air verses a still container of
3. Mustad 39960D (Duratin) Tuna Circle hooks , 13/0,seawater.
rigged baits for marlin & sailfish,Dispelling My Duratin Myth
4. Maruto SS1920-2X Stainless Steel, 6/0, mall toThe results were a bit of a surprise. The Stainless
medium skirted luresSteel hooks performed as expected however the
5. Gamakatsu Live Bait hooks, High Carbon Steel,6/0,Duratin hooks lasted significantly longer that I thought
Deepwater jigging / Bottom fishingthey would. In fact, after 21 days suspended in salt
6. Mustad 7794BD Treble, 1, Small Bibbed Minnowswater, despite some surface rust, they were as strong
Each hook was crimped to 100lb monofilament lineas ever. Even the barbs were still intact.
using a 1.6mm Brass double sleeve and suspended in aCONCLUSION
container of seawater. Containers were made fromIn reality, a hook in a fish's mouth would have constant
cutting the top off plastic drinks bottles, screwing themmovement of seawater over its surface which would
down to a bench and using the tops to hold theaccelerate corrosion however the only way for us to
bottoms. The seawater was refreshed daily and thetest this would be to suspend the hooks in a live well.
hooks inspected at the same time each day. To test,I didn't want all that rust in my live well !
each hook was removed, held with the shankI had observed that a Duratin hook, used at sea and
horizontal, point down and a weight of five poundsput away without a wash in fresh water is basically
was suspended from the bend of the hook near theuseless within days. This led me to believe that, if left in
barb to see if it had weakened sufficiently to bend ora fish, the hook would deteriorate rapidly and fall out
break. In the case of the treble, the weight waswithin days.
suspended from only one of the hook bends.I was quite wrong. Duratin hooks survive much longer
RESULTSthan you think. We will continue to favour Duratin
Gamakatsu SL12S - Corrosion started within 1 dayhooks because they do rust out much faster than
Mustad 7766D - Corrosion started after 2 daysStainless Steel hooks however I stand corrected on
Mustad 7794BD Trebble - Corrosion started after 2their rates of corrosion if lost fish. Its not a matter of
daysdays, it's a matter of weeks.
Mustad 39960D - Corrosion started after 3 days