Dive Computer Expert Reviews
Saving Your Precious Time And Finding The Best Dive Computer For You

Dive computer reviews are perfectly organized and consist of fully researched information and ratings of Aeris, Cressi, Mares, Oceanic, Sherwood, Suunto, Tusa, and UWATEC/ScubaPro brands.  In Catalogue Section you may compare any models side-by-side and select dive computer according to your needs! Join thousands of happy customers!


Tusa IQ-850 DC Sapience II: Diving In New Underwater Adventure

Tusa IQ-850 DC Sapience II: Diving In New Underwater Adventure

Tusa IQ-850 DC Sapience II is a high-tech elegant dive computer with 2 Nitrox mixes and 3 dive modes. You will be well-informed by its large display and vibro-alarm. Automatic altitude adjustment, personal safety factor setting and Safety stop reminder - all help us enjoy diving in full extent.

General Information
User Interface
Your Review



Most dive computers today are made as digital watch computers or console style but Tusa IQ-850 DC Sapience II is quite unusual model from the line of Tusa dive computers. It is made as a wrist unit with large, thin and dot-matrix monochromic display. Other distinctive features are vibration, during alarms or warnings, and big Nitrogen Loading Tissue Bar Graph on the top of the screen.

Tusa IQ–850 DC Sapience II is based on Swiss – Bohrer algorithm with 12 tissue compartments. Tissue Loading Bar Graph that I mentioned above calculates, controls, and shows during a dive or on surface, each tissue compartment individually.

If you are very cautious diver – it is an extra-benefit for you, because you may watch how your process of gassing and off-gassing is going and you may set curtain personal safety rules, according to its display! I found it pretty nice addition to other features that this dive computer has on offer to us!

I may say that Tusa IQ–850 is suitable not only for advanced recreational divers, but for beginners as well, who are not afraid to spend some time to read carefully manuals and learn of how to squeeze maximum out of this miracle of modern technology!


Tusa DC Sapience II IQ-850 Features Card

Copy this Tusa IQ-850 Key Features & Alarms Card for your Reference and Share with your friends and buddies!



Benefits of using Tusa IQ-850 DC Sapience II dive computer

  • you will be definitely standing out of other divers with the unique design and look of Tusa IQ-850 DC Sapience II dive computer;
  • you will get sophisticated and elegant dive computer that has 3 dive modes for diving with Air, Nitrox, and using technical gas mixes in Gauge;
  • you will have the only dive computer that has vibro-alarm;
  • you will be able to enter technical diving with double Nitrox mix;
  • you will be able to replace battery yourself and keep settings safe with battery 'hot swap' function








User Interface
3 buttons
Dive Modes
Air, Nitrox, Gauge
Vibro - alarm
Swiss – Bohrer
Number of Gas Mixes
Air, 21% - 99%
1.2 - 1.6 ATA
Air Integration
Safety Stop (SS)
Deep Stop (DS)
Conservative Factor
Altitude adjustment
Gas Switching
Dive Planner
9 - 57 meters
Logbook Capacity
25 dive hrs with 30 sec sampling rate
Max Operational Depth
100 meters
Backlight duration
5 sec
Sampling Rate
factory pre-set
User Replaceable Battery
Battery 'hot swap'
PC Interface
2 years










Tusa IQ–850 DC Sapience II dive computer has 3 control buttons to set up and view dive data and one more button is for wet activation. 3 bar graphs are available to supply us with information about nitrogen and oxygen loading, and ascent rate:

  1. Pressure Gas in Tissue (PGT) Bar Graph – graphically represents nitrogen loading of tissue compartments during gassing and off-gassing. It controls and displays all 12 tissue compartments and ‘plus’ or ‘minus’ signs make it easy to understand when tissues are loading or off-gassing.
  2. Ascent Rate Bar Graph – represents how fast you are ascending, if ascent rate is faster than allowable maximum – dive computer will display full set of segments, notation SLOW and vibration and audio alarms;
  3. Oxygen Limit Indicator (OLI) – shows current level of oxygen toxicity and if it is high – dive computer gives and audio and vibro alarms.







Now we will set our dive computer to get ready for underwater adventure. Even though manuals could be structured better than they are, after reading carefully and practicing with buttons sequences – you will become master of that!


Tusa DC Sapience II IQ-850 Fine-Tuning Card

Copy this Tusa IQ-850 Fine-Tuning Card for your Reference and Share with your friends and buddies!


Tusa IQ–850 DC Sapience II has Dive Planner that calculates No-Decompression Limits (NDLs) for the depth that you entered and according surface time you specified, and nitrogen and oxygen loading. It displays not only NDLs, depth, all applicable icons and notations, Pressure Gas in Tissue Bar Graph, and O2 level, but also surface time required for you to dive after and reach your desired depth.







It is all pleasure diving with Tusa IQ–850 DC Sapience II. Large display shows large digits and all dive data is grouped very well and everything is intuitive – just glance down to the screen and you get last update!


Tusa IQ-850 DC Sapience II: Diving With Air & Nitrox


Tusa DC Sapience II IQ-850 NO-DECO Card

Copy this Tusa IQ-850 No-Decompression Displays Card for your Reference and Share with your friends and buddies!


In No-Decompression mode upon reaching certain conditions, dive computer may give us Safety Stop prompt with ‘Safe Stop’ notation and countdown timer. If we miss recommended Safety Stop – there will be no penalty.

As other dive computers, Tusa IQ–850 has few other useful warnings – Ascent Rate alarm, High PO2 and High Oxygen Limit Indicator (OLI) warnings:

  1. Ascent Rate Indicator is located on the left side of display and it will give notation SLOW, vibro and audio alarm if our ascent rate will be faster than maximum allowed at certain depths;
  2. High PO2 will be activated if PO2 for gas in use will get 1.4 or 1.6 bar level at certain depths;
  3. High OLI warning is activated when oxygen toxicity level will reach 80% and when PO2 reaches 1.6 bar at certain depth


When we exceed our No-Decompression Limits – Sapience II activates Decompression dive mode and all calculations are related to this mode from that moment.

Tusa IQ–850 dive computer will display few stops with appropriate depths and times to complete decompression. In addition to Elapsed Dive Time, current depth, FO2 values and other dive data display shows following decompression attributes:

  1. DECO notation;
  2. Total Ascent Time (TAT);
  3. Decompression Stop depth and Decompression Stop time


When we finish with first stop, dive computer will display another one at shallower depth. We need to ascend safely to that depth and stay at that depth or a bit below until stop timer reaches ‘zero’, and so on. When decompression process is completed – we may resurface safely.

If in some reason you didn’t perform decompression – dive computer would lock itself and display would freeze. Only after 48 hours it will wake up in Time mode, which is default mode for Sapience II.


Tusa IQ-850 DC Sapience II: Diving In GAUGE Mode

This dive computer has 3rd Dive mode – Gauge. In this mode Tusa IQ–850 can be used as a dive timer and depth gauge only. Display has very simple layout:

  1. Elapsed Dive Time (EDT);
  2. current depth;
  3. current time;
  4. water temperature







After our diving with Tusa IQ-850 DC Sapience II it is time to resurface and check out our logs, history and download dive data to PC:

  1. Logbook can store 25 hours of dive time or up to 25 logs with 30 seconds sampling rate. It is pretty extensive and has 2 pages of information;
  2. History saves total number of dives, total number of dive hours, and maximum depth reached;
  3. PC download – using special optional interface unit and software you may download dive data to PC for viewing, organizing, and printing it







Tusa IQ-850 DC Sapience II: What Divers Say


  • easy to set and use, after you figure out manual;
  • 2 Nitrox gas mixes;
  • vibro-alarm is handy option and noticeable through the sleeve of every suit;
  • display is clearly seen with large digits



  • no air-integration;
  • manual is poorly structured & written


Tusa IQ–850 DC Sapience II belongs to high-tech dive computers in nowadays scubadiving market. It is well suited for advanced recreational divers, but still may be considered as a ‘buddy’ by beginners, who are prepared to put some time to study manuals and explore possibilities of this remarkable dive equipment.

My only negative opinion is how manuals were written and structured. Or maybe it is just a new documents’ standard from Tusa?

And underwater, to press the buttons, you need to bend wrist a bit down – this is another little inconvenience.

Other than that – we didn’t pick up any troubles while diving with Tusa IQ–850. Solid and reliable dive computer that got quite a few compliments from people around!


Tusa IQ-850 DC Sapience II dive computer
Tusa IQ-850 DC Sapience II

Dive-Computer-Wizard Rating
golden star golden star golden star golden star half star


If you like high-tech dive gear – you may consider buying Tusa IQ–850 DC Sapience II. From specs, features and price point of view – it is a perfect combination!



Add comment
Marshall, 12 February 2016 00:39
Recreational Diver: Tusa IQ-850 - Pros & Cons

I have pretty bad Tinnitus and can't hear most alarms which led me to the TUSA IQ-850 vibrating computer. If one is paying attention, alarms shouldn't be an issue. As a new underwater photographer it's much easier to get side-tracked and an alarm can be handy, even though I've gotten much better after experience of checking my computer much more often. The vibration feature works quite well (I can feel it through my wetsuit sleeve) and I can set a timer to buzz me at different times and depths as sort of a reminder where I'm at on the dive.

I also bought the computer interface and a cheap USB cable for my PC and it works great. Mind you, there is no Mac program, only Windows, but I loaded a simple Parallels PC SW which can emulate Windows code and it works with the unit.

My only complaint for this unit is the night dive back-illumination. You can barely see it except in total pitch blackness. I sent it in thinking I had a faulty unit, but TUSA said it's a design issue and doesn't get any brighter? Wierd they would sell it that way? So on night dives, I have to swing my photo rig around to read it which is a bit awkward to do. Shame it doesn't glow bright like a Casio watch. It's the only dive computer I could find that vibrates though. Given Tinnitus is pretty common with older divers, I/m surprised there's no more models.

Overall I'm happy with the computer. Easy to read during the day and lots of information.

Edward Martin III, 19 June 2014 15:25
Few words about Tusa IQ-850 DC Sapience II

I very much like the vibration feature. I would like to know how detailed the dive profile is before I spend money on the PC cable. I'm unclear why a $114 cable is needed to interface the device to a PC. 

I very much dislike the manual. If this was for a stereo in 1972, I wouldn't care, but this is for a device that will help keep me alive. The manual is my interface to it. First-year tech writers can do a better job than this - it's really horrible.

Harley, 7 November 2013 09:48
Tusa Sapience - Great Dive Computer & Horrible User Docs

Tusa IQ-850 Sapience is my buddy since 2010. It is very reliable dive computer with very distinctive look! I like everything unusual, so that's why I've bought it.

After struggling with user manual trying putting all together, I've finally got all bits and pieces after quite some time. And this is my main complaint about this instrument.

Brent, 5 March 2012 04:34
Tusa Sapience Has The Best Display Readability!

I had my Tusa IQ-850 for about a year. I was looking for dive computer with large display with good contrast, because my eyes getting older and I wanted to know dive data just by glancing down, not staring at my computer! I didn't need picture uploading feature or air integration, so I selected Tusa Sapience.

Sapience is quite unusual dive computer and I we needed to get used to one another, it is not bulky - it is just one huge display that is sitting on my wrist! And it is all I wanted - all digits are sharp clear in different angles, and all display layout is very understandable.

Large nitrogen bar graph - that's a perfect safety addition to possibility of setting Safety Factor programs. With its individual compartments displayed separately it is much easier for me to control diving - I try to avoid decompression dives, because of my age. And I managed it perfectly so far!

I couldn't think about any of negatives, maybe just user documentation should be written much better and PC interface might be included with dive computer, or sold a bit cheaper, and that's all, I think.

Add comment