Divers love an adventure and historically one of the most exciting things to do in the undersea world is finding artifacts, wrecks, and other treasures. One of the best tools to get you started is a metal detector. Many models have been in use for land-based metal detection for a long time. Recently waterproof models have been improved and developed for use by recreational divers and others who are not supported by high-level technical salvage operations.
Below a number of models of various levels of sophistication and depth ratings are described and reviewed with videos of introduction and a comparison table. After that is a buying guide that explains simply some of the key specifications to help you make the best choice for your needs.
Best Underwater Metal Detectors of 2020
- Quest Scuba Tector
- KKMoon Metal Detector
- Fisher CZ21-8 Underwater Metal Detector
- Garrett Sea Hunter Mark II
- Fisher 1280-X Aquanaut
- Pulse Dive Scuba Detector
- TTLife Pulse Induction 750
This handheld lightweight model is good in saltwater and to depths up to 60 meters (200 feet). With a lost alarm, LED flashlight, and lanyard, it is difficult to lose track of. This model has a reputation for a high level of sensitivity, a reasonable penetration depth, comes in orange or black, and is reasonably priced.
- VLF (Very Low Frequency) technology superior for land-based searches
- Handheld with an ergonomic, ribbed body
- Two-button control with a target locking function
- Lost alarm, LED flashlight, and lanyard attachment
- Comes in black or orange
- Built-in Lithium Polymer battery included
- Waterproof to 60 meters (200 feet)
This model uses Pulse Induction technology and is waterproof to depths of 98 feet in saltwater. It has an easy to use tilt system to turn on and off and signals the presence of metal with a vibration in addition to an LED light. Superior microprocessor controlled design needs no adjustment and the detection distance is maintained through the life of the battery. Low-priced, it is available in easy to see orange or yellow with a holster.
- Pulse Induction technology
- Vibration and LED light signals
- Equipped with a tilt to turn on and off system, with no other adjustments necessary
- Advanced circuitry maintains stable detection depth throughout the life of the battery
- Waterproof to 98 feet
- Comes in yellow or orange with a convenient holster
- Waterproof to 98 feet
Fisher CZ21-8 Underwater Metal Detector
This sophisticated Pulse Induction technology model will delight technical divers with a waterproof capability to 250 feet of saltwater. The control box has a volume control to boost weaker signals and a choice to use precise settings to identify metal-type or auto-tune mode. It has a collapsible pole assembly to adjust comfortably for land or underwater use and waterproof headphones.
- Pulse Induction technology
- Choice of auto-tune mode or 7-settings for identifying the metal type
- 3-Tone audio target ID
- 8 and 10-inch coil options
- Waterproof headphones
- Collapsible pole assembly
- Waterproof to 250 feet
The Garrett Sea Hunter Mark II is a durable and reliable model that is lightweight and fairly sophisticated at a moderate price for the quality. Rated to 200 feet in depth this Pulse Induction model has two modes for metal discrimination with an adjustable audio threshold, and waterproof headphones, along with long and short stems and a hip mount belt for more comfortable usage.
- Pulse Induction technology
- Adjustable audio threshold
- Two operating modes for metal discrimination
- Hip mount belt/pouch for long searches
- Lightweight
- Waterproof headphones
- Has long and short stems
- Waterproof to 200 feet
Unusual for a VLF model, the Fisher 1280-X Aquanaut has a low 2.4kHz frequency and is rated to 250 feet in fresh or saltwater. The battery charge lasts much longer than most at 75 hours. It also has waterproof headphones, sensitivity adjustment, and a belt mount. With so many advanced features the pricing is pretty low.
- VLF (Very Low Frequency) technology superior for land-based searches
- Battery life to 75 hours on a single charge
- Sensitivity adjustment, manual ground balance, discrimination settings
- Belt mount
- Waterproof headphones
- Waterproof to 250 feet
This lightweight handheld Pulse Induction model is waterproof rated to 60 meters (200 feet) and full of features. It has audio, vibration, and LED indicators available for detection, rapid one button retuning, and a lost alarm, LED flashlight, and belt holster security lanyard to keep from losing track of it. While headphones are not included, a built-in wireless module is compatible with a popular set. Available in yellow or black, pricing is fairly low and includes a 2-year warranty.
- Pulse Induction Technology
- Handheld
- Detection alerts include audio, vibration, or both with LED indicator in addition
- Lost alarm, LED flashlight, and belt holster security lanyard
- Rapid retune with the push of a button
- Lithium Polymer battery included
- Built-in wireless module compatible with Nokta Makro 2.4 GH Green Edition Wireless Headphones
- Waterproof to 60 meters (200 feet)
- Available in black or yellow
- 2-year warranty
This simple, compact Pulse Induction handheld model is easy to use and waterproof in fresh or saltwater to 100 feet. It has automatic tuning, vibration and LED alerts, and high sensitivity though it does not differentiate between metals. It has rugged sealed construction with a wrist strap and belt ring for security and a built-in low battery sensor. Pricing is fairly low.
- Pulse Induction Technology
- Handheld
- Tilt on/off switch-free on/off system
- Detection alerts include vibration and LED alerts
- High sensitivity pinpointing, no discrimination between metals
- Automatic tuning
- Low battery indicator
- Wrist strap and belt ring
- Easy 9V battery installation, battery not included
- Waterproof to 100 feet
Underwater Metal Detector Comparison Chart
| Picture | Underwater Metal Detector | Type | Depth Limit | Price |
|---|---|---|---|---|
| Picture | Underwater Metal Detector | Type | Depth Limit | Price |
  | Quest Scuba Tector | Very Low Frequency | 60 meters/200 feet | $$ |
  | KKMoon Metal Detector | Pulse Induction | 98 feet | $ |
  | Fisher CZ21-8 Underwater Metal Detector | Pulse Induction | 250 feet | $$$$$ |
  | Garrett Sea Hunter Mark II | Pulse Induction | 200 feet | $$$$ |
  | Fisher 1280-X Aquanaut | Very Low Frequency | 250 feet | $$$$ |
  | Pulse Dive Scuba Detector | Pulse Induction | 200 feet | $$ |
  | TTLife Pulse Induction 750 | Pulse Induction | 30 meters | $ |
How Do You Choose the Best Underwater Metal Detector?
Detection Type – There are two types of metal detectors suitable for underwater detection, Pulse Induction (PI) and Very Low Frequency (VLF).
- Pulse Induction (PI) systems send bursts of electronic pulses into the ground and then if something metallic is hit, a signal is sent back. These are generally better than VLF models in salt water because they are unaffected by high levels of mineralization. They have good sensitivity to valuable minerals and can locate deeper targets though they are less discriminating and more likely to locate unwanted targets and trash.
- Very Low Frequency (VLF) models detect on a low frequency which makes detection more discriminating. They can ignore mineralized soil and select more valuable metals rather than bottle caps or a nail with a sensitivity toward more valuable metals, jewelry, and coins. With some exceptions, they tend to be less suitable in saltwater due to higher levels of mineralization but are often lighter and cheaper.
Water Depth – For the purpose of this review on a scuba diving website, the models selected are all waterproof to at least 98 feet. There are metal detectors only for land use and those for shallow submersion just below the surface and others that are waterproof rated for depths graduating up to 250 feet or more.
Versatility – Generally the models most effective in saltwater will use PI technology. Detectors that have waterproof ratings are obviously the choice for underwater work. These underwater devices will also detect effectively on land but you will have to keep in mind that they are also often heavier to counteract buoyancy and otherwise configured for ease of use in the underwater environment. If you plan on significant use on land you may want to consider a model dedicated to that.
Accuracy – This refers to the depth below the surface of the ground or bottom that the device can detect metals. The ocean bottom is quite malleable due to currents, tides, and the weather which can move it around potentially putting more material on top of valuable items you might want to locate. The deeper the detection capability, the more materials that can be discovered. Many of the videos show testing of metal detectors to demonstrate this with various metals.
Underwater Accessories are not always essential but can add greatly to the experience. Here are a few.
- Underwater Headphones can make faint detection signals much more distinct especially when ambient sound levels are high.
- Steel Trowel – This can make digging a lot more effective.
- Mesh Pouch – When you recover many targets, you have a convenient place to put them.
- Chest Harnesses or Belts – Larger models often include something like these in the package to allow more control especially for environments with surge or current.
Feedback and Comments
I hope you found this post on the best underwater metal detectors interesting and useful. If you have any questions or ideas, please feel free to share them in the comments section. If there is no comments section directly below, click here: >>comments<<