Chris's Metal Detecting Page

Review of the Tesoro Tiger Shark is mainly about [what else?] mineral collecting, but Treasure Hunting is somewhat related, so here goes...

When I decided to graduate from an older White's, I picked up a Tesoro Tiger Shark.  Many people out there seem to be wondering how the Tiger Shark does in the ocean.

This review was originally written when I'd had little experience with the 'Shark.  The article has been updated to reflect not only the time spent at the beach, but also some fresh-water trips and land detecting with this great unit.   First let's get the salt-water question out of the way, then we'll look at fresh water and land detecting.   We'll also look at the Tiger Shark next to the other choices out there, and consider what's best for each intended use.

Chapters (scroll down or click link):

1.  Tiger Shark In Salt Water
2.  Tiger Shark In Fresh Water
3.  Tiger Shark On Land!
4.  Putting It All Together

Tiger Shark in Salt Water

If you're inclined to "skim" or came here looking for the bottom line, here it is:  the Tiger Shark is GREAT for fresh water and for land & beach detecting, and OK for salt water.  (And you can really help support this free website by purchasing your Tiger Shark through this link.) 

If detecting in salt water is your primary goal, you might want to look into a pulse induction (PI) machine such as the Sand Shark (currently about $577 here).  Though PI lacks discrimination, experienced PI users are very good at picking out coin- and ring-sized signals.   Pulse induction goes very deep and is totally unaffected by saltwater conditions.  Or, consider a Minelab Excalibur II or a Fisher CZ21-8.  These cost a lot more than the Tiger Shark or Sand Shark, but that's the way it is with non-PI detectors that work well in salt water.  To offer discrimination and completely cancel out the effects of salt requires some fancy circuitry.  You pay a lot, and it can't go as deep as PI, but you get the ability to discriminate. 

The Tiger Shark is a single-frequency VLF detector.  That means moving salt water (i.e., waves lapping over it) tends to cause falsing.   The fact that you can even take a single-frequency VLF into the ocean and not have it freak out to the point of uselessness is pretty remarkable.  The engineers who designed the Tiger Shark seem to have done everything possible to minimize this sort of thing.  (It's still no Excal II, but it's usable). 

I put the TS through its paces at the ocean a few times, and here's what I found.

The Tiger Shark actually performs pretty well when there's not that much black sand, even with the sensitivity on medium.  I drove around until I found a beach where the sand appeared relatively free of the stuff (well, sort of).  The Tesoro still had a little bit of chatter and "falsing" in the salt water, but it was pretty obvious when it got a good signal.  A corroded bottlecap about 6-8 inches deep gave a very loud, definite, repeatable signal.  This couldn't be confused with a false reading.   There was no mistaking it.  The same thing happened with a piece of an aluminum beer can and a couple of nails.

If you are hunting the most heavily-mineralized black sands, the factory-preset Tiger Shark will have an overwhelming number of false signals in the saltwater, especially when the ocean churns up the sand and carries it over the coil.  The way around this is (1.) turn down the sensitivity adjustment, which is inside the case (don't open the case anywhere near the water!) and (2.) move the coil as slowly as possible.  Yes, the detector is usable in salt water, but it takes a little while to get used to the constant clicks that moving salt water and black sand particles cause when they move across the coil.  Once again, reduced sensitivity is the answer.

The lack of coins from the ocean field test was not because the detector couldn't handle it, but because the conditions weren't right.  Normally, coins and other dense objects work themselves downward very quickly.  Within just a couple hours, they're out of detector range altogether.  Somewhat less-dense objects (bottlecaps, for example) are in a zone that's not as deep.  This is the zone you're going to be hitting with most any detector you take into the ocean... UNLESS you are lucky or skilled enough to find a "trough" where the ocean has exposed the denser objects.  These troughs do not last long. 

If you do not find one of these troughs, the wave action will have worked coins and rings much farther down into the sand than a metal detector can reach. 

The Tiger Shark will detect them if they're there and in a reasonable depth (say, 6-10 inches).  Based on my finding a bottlecap, small washers, aluminum can fragments, and some nails, I'd have found coins if they had been in that layer.  The point here is that the Tiger Shark could pick out small targets and get consistent signals, even if there was some chatter.  

The detector seems to have run into a couple earring backs or tiny pieces of foil, because a couple times there were good signals that kept escaping the scoop.   This was not falsing;  there was something there.   It's easy to find pieces of metal so small that they fall right through the mesh.

The most important thing about any signal is salt water is whether it's repeatable.  I have found that false signals tend to occur under the following conditions in the ocean:

1.  at the endpoints of each sweep
2.  when you accidentally hit bottom with the coil
3.  when you move the coil too abruptly
4.  when there is too much black sand and bits of rusty iron all over the place

There's a simple way to deal with the first three conditions:  Just focus on the middle portion of each sweep when you hear the signal.  If you get a signal that happens only at the endpoints of your sweep, not in the center, it is a false. 

The fourth condition might mean you'll have to try a different beach, but turning down the sensitivity can help a great deal.  You should still be able to find coins, but you won't be picking up every tiny piece of crumpled-up foil or flake of rusty iron.  Of course, some of those small-metal signals could be thin gold chains, so maybe you'd better dig them!

Once you master the learning curve for dealing with false signals, processing the audio and visual data through the best computer in the world (your brain), you can get good results with this metal detector in the ocean.  If you try different areas and settings, you can develop a good feel for these techniques in as little as two or three trips out.

The unit was clearly able to handle the salt water, but the ocean became too rough for my liking as clouds rolled in and it became windy.  Too many facefuls of water finally took their toll.  I can't count how many times I dropped the scoop or how many times a wave knocked the coil flat up against the shaft while I was trying to detect.   Fighting the waves can take the starch out of a person pretty quickly.

I could see the Tiger Shark being more usable in a dive situation where there wasn't black sand being swirled around with every wave.   That, and there'd be no buffeting of the coil, which gets kind of annoying with any metal detector.  (Surf detecting sounds pretty rad until you actually try it.  It's a lot of work.)  Anyway, if this all sounds doable to you, and you want to give the Tiger Shark a try in the ocean, you can get one here.  Otherwise, keep reading to see why it's an even better detector in freshwater and on land.


Tiger Shark in Fresh Water

Some people have no trouble detecting in the ocean.  I'm not talking about the choice of detector either.  I'm talking about getting slapped with waves constantly, not being able to keep your footing, having to watch out for undertow and riptides, etc.  There are some aspects of ocean detecting that are a blast, but fresh-water detecting is generally much more tranquil.  After a day when the sky turned gray and the ocean turned rough (while I was still in it), I decided I might prefer detecting lakes instead.

We headed out to a lake up north.  Despite the mosquitos, we had a great time.  The Tiger Shark revealed a Mercury dime in the first ten to twenty minutes.  On a second trip, after being in the lake for a while and digging a few wheaties, I found a 10kt gold ring.  This wasn't a side-by-side comparison with another detector, but it was clear the unit was getting good depth.  Having used a super heavy-duty scoop, I found that it took sometimes two or three full scoops to bring targets up from the bottom of the lake.  I don't know what depth that is, but it's deep.  While some sand falls into the hole after each scoop, it's probable that the targets were a good 7+ inches down.  Some of them, maybe 10 inches down.

Pinpointing wasn't hard, because the white coil is easy to see in the water.   This was a good design move.

Using the Tiger Shark in fresh water is a real joy.   Submersible detector, submersible headphones.  It makes a distinct "quack" sound when you find a target.  Well, not really a "quack", but it reminds me of one.  It's a beep that has a particular quality.  Discriminated targets give a more broken-up sound, as you'd expect.  I found that using the Tiger Shark in All Metal (Fast) mode was also a lot of fun in the water.  That will uncover more junk, but more coins too.   I usually use Disc mode, though.

This machine is an absolute winner in freshwater.  I really can't think of any detector that I'd rather use there, and I say that as a pretty big fan of Minelab and Fisher metal detectors.

Tiger Shark on Dry Land... or Soaking Wet Land, if you prefer

The Tiger Shark achieves good depth on land.  It doesn't get the depth of a Tejon (not many detectors do), but it's pretty respectable in its own right.  In a heavily-pounded park, I found two different Barber dimes, each at 7" to 7 1/2" depth.  The signals were not loud, but they were consistent.   What's remarkable is that I had gone over the same spot with two other detectors and missed these coins.

I didn't see any other detectors around that day.  That might be because it was raining steadily.  This is one of the big secrets of finding the deep stuff with a Tiger Shark:  you can take advantage of the saturated ground when others can't.   By the time it stops raining, the ground is already drying up.  You with your Tiger Shark can hit it while the ground is soaked.  And you'll have more fun doing it, because this detector is a lot lighter than a Minelab Excalibur or a Fisher CZ-21.

The Tiger shark is just as pleasant to use on land as it is in your favorite lake.  What's really nice about this unit as a land detector is that you don't have to worry about a plastic bag or other makeshift rain covering for it.  If you're out detecting and it starts to rain (which it so often does), you won't have to quit on account of the machine.  That can mean a lot if you took the day to drive somewhere you can't easily return.   If I were going to a place like that, such as a special one-time-only dig, I wouldn't hesitate to grab the Tiger Shark.  Bring along a rain poncho and a change of socks just in case. 

Above:  The Tiger Shark...
for when you want to detect your yard.
In the pouring rain.
At night. 
In November.
(Don't get hypothermia, please.)
By the way, mine says "Tesoro" because I cut out the bumper sticker
and plastered it on the coil.  When you buy a Tiger Shark,
the coil is plain white.

There is a unique kind of joy in looking out the window, seeing a torrential downpour, and actually saying "I'm going metal detecting!"  Sure, you'll get filthy, your shoes will be caked in mud, your pants will be caked in mud, but so what?  There be treasure out in them hills, matey. 

Obviously, don't go out and get hypothermia (this can be fatal), and don't dig a place into a muddy mess.... but the point is that the Tiger Shark can easily handle the weather. 

How many detectors can you safely hose off with water when you're done for the day?  Headphones and all!  

Putting It All Together

The Tiger Shark:

- Is waterproof to 200 feet, making it extremely versatile. 
- Does well on dry land and great in the rain
- Is easy to use.  My wife has taken mine and won't give it back.
- Makes a satisfying beep when you find a target (I really like the sound of this machine).
- Has great discrimination
- Has manual ground balance (a very good thing!)
- Uses AA batteries and gets good battery life.
- Has waterproof headphones included (permanently attached)
- Is one of the few detectors that can find thin gold chains and tiny nuggets.
- Weighs less than most other waterproof metal detectors
- Is one of my favorite detectors.  Ever.

The Tiger Shark is great on everything up to and including wet salt beaches.  As we've already seen, once you get into the ocean the Tiger shark may false too much for your liking.  As we've also seen, there are ways to manage it.  If you just don't want to deal with falsing at all, here's where I'd consider another detector.   My three favorite choices would then be the Minelab Excalibur II (currently about $1,500 with 8" coil here, or 10" coil here), the Fisher CZ-21 (currently $1,125 with 8" coil), or Tesoro's own Sand Shark (about $577 at the moment).   Note that the Sand Shark is a pulse-induction machine and has no discrimination, so you're digging everything there.   Pulse Induction units get the best depth (by far), but get ready to dig a lot of nails and stuff.

Outside the "moving salt water" scenario, the Tiger Shark is an excellent choice.

I'd say I wouldn't trade my Tiger Shark for any other machine, but my wife already claimed it anyway.  She then proceeded, on her first or second day, to find a bunch of silver coins at a house site, including a Standing Liberty quarter.  I think she found more coins than I did.  (But whatever.  My favorite method of coin hunting involves signals so faint that it's like ESP, and you could spend days looking for just one.  That's my excuse.)

You can show your support for this website by shopping through any of the links on here.  Get your Tiger Shark or any other detector, or pretty much anything else through these links, and it helps me to keep bringing you original, informative articles. 

Thanks for reading.  Happy metal detecting!


Site Map / Articles Index

If you surfed in here from somewhere else and wonder where you are, this site is mainly about collecting Rocks and Minerals.  But you just happened to wander into the Metal Detector portion of the site. 

Back to Chris's Mineral Collecting Page