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Aeris A300 Ai Is For Savvy Tech Divers

Aeris A300 Ai Is For Savvy Tech Divers

Aeris A300 Ai - new advanced hose air-integrated dive computer for advanced divers and bold beginners.  It supports up to 4 different Nitrox mixes, has Dual Algorithm, integrated digital compass, and improved user interface.

General Information
User Interface
Your Review



Aeris A300 Ai was introduced to our scubadiving market at the very beginning 2012. This step clearly shows that Aeris always trying keeping up with the greatest demands of the divers and do this very well!

This new advanced instrument can be recommended dive computer for technical diving, as it supports up to 4 different Nitrox gas mixes, has integrated digital compass, improved user interface and Dual Algorithm. And by the way, Aeris A300 Ai may easy fit any beginner in scubadiving, who is serious to grow as a diver.


Aeris A300 Ai Functions Card

Copy this Aeris A300 Ai Features & Alarms Card for your Reference and Share with your friends and buddies!


Aeris A300 Ai is an advanced hose air-integrated dive computer with possibility of setting up to 4 Nitrox mixes and integrated digital compass. Instrument was built with Dual Algorithm that means - we may choose between conservative and more liberal diving to accomodate our particular needs. Air integration works only for the 1st tank and therefore all measurements and alarms are valid only for this cylinder.

Algorithms are listed below:

  1. Pelagic DSAT – use it for liberal diving, and to add more conservatism you may adjust TLBG alarm and set your Personal Conservative Factor to ON.
  2. Pelagic Z+ - use it for conservative diving, and by choosing this algorithm, you will increase conservative factor by 15 – 20% right away. This option is a great benefit for those people who involved in frequent and challenging diving conditions, divers who are overweight, and people who dive in cold water conditions or those who didn’t dive for a long period of time.



Benefits of using Aeris A300 Ai dive computer

  • you will always keep your underwater directions correct while diving with Aeris A300 Ai, thanx to its integrated digital compass;
  • you will always have steady data about your air consumption, thanx to its hose air integration;
  • with Aeris A300 Ai wide customization options you can dive in pretty different scenarios, liberal or conservative, recreational or technical, and down to depth of 120 meters;
  • you can always replace battery by yourself without losing piece of data;
  • you may update firmware by yourself, whenever it's available


Aeris A300 Ai is a praiseworthy successor of Aeris Atmos Ai, which proved to be very reliable buddy and actually continues of doing this!








User Interface
3 buttons
Dive Modes
Air, Nitrox, Gauge
Integrated Digital Compass
Dual: Pelagic DSAT & Z+
Number of Gas Mixes
Air, 21% - 100%
1.0 - 1.6 ATA
Air Integration
Safety Stop (SS)
Deep Stop (DS)
Conservative Factor
Altitude adjustment
Gas Switching
Dive Planner
9 - 57 meters
Logbook Capacity
24 most recent dives
Max Operational Depth
Air/Nitrox - 100 m; Gauge - 120 meters
Backlight duration
5/10/15 sec
Sampling Rate
2/15/30/60 sec
User Replaceable Battery
Data Retention
PC Interface
2 years











Aeris A300 Ai has 3 control buttons - Mode(Menu), Advance(Add), Select(Save). User interface is quite easy to get familiar with, but first one will need to read thoroughly manuals to learn how to manage comprehensive set of menus. Interface has "Step Back" feature, which we found very convenient during set up - it saved lots of time!

Visual information is accompanied with 2 Bar Graphs - TLBG on the left side for nitrogen loading and VARI that shows ascent speed.

TLBG consists of 5 bars to address 3 level of nitrogen loading:

  1. No-Deco Normal zone - 1-3 bars;
  2. No-Deco Caution zone - 4th bar;
  3. Deco zone - all 5 bars

During surface operations or diving Aeris A300 Ai dive computer has main and few alternative displays to keep the diver well informed.

Integrated digital Compass can be accessed from Surface Main or Dive Main screens. Compass operation has limited timing and when there is only 15 seconds left for Compass to function (time displayed on the screen) - diver may extend the operation by pressing S-button. It will give extra 2 minutes to stay in Compass Mode.







Now we will set up our Aeris A300 Ai and be ready to get wet!

Main Menu consists of 8 sub-menus where we may access our dive logs, check out history, plan the next dive, set our dive computer, choose dive mode, or access dive preview screen.

Set Menu of Aeris A300 Ai dive computer has pretty extensive number of sub-menus, saying precisely - 7 of them, as you may see on the following Fine-Tuning Card.


Aeris A300 Ai Fine-Tuning Card

Copy this Aeris A300 Ai Fine-Tuning Card for your Reference and Share with your friends and buddies!

As computer has Dual Algorithm feature – it means that you may choose between liberal and conservative diving. And you may make A300 Ai even more conservative by setting Tissue Loading Bar Graph (TLBG) alarm by adjusting number of bars and setting Personal Conservative Factor (ON/OFF). Setting and adjusting these values will move you further away from exceeding No-Decompression Limits (NDLs).

After we set Aeris A300 Ai, we may plan the next dive and scroll through the depths at range 9 - 57 meters. Dive computer shows allowable No-Deco depths and bottom times depending on divers nitrogen loading and oxygen saturation from previous dives, and also Personal Conservative Factor.

If needed - we may access dive preview screen from the Main Menu to check some of our settings before diving. After that - we are ready to go underwater!







Before going into water we need to set Wet Activation to ON and dive computer will automatically activate Dive Mode upon entering water.

Aeris A300 Ai: Diving With Air & Nitrox

Main Dive screen displays lots of dive data and it depends on how we set Aeris A300 Ai, whether we set it for Air or Nitrox, selection of Algorithm, enabling Personal Conservative factor, etc.

Below is the illustration of what I got when dive computer was set for Nitrox, Personal Conservative factor is ON, PZ+ algorithm chosen and diving in No-Decompression condition:


Aeris A300 Ai NO-DECO Card

Copy this Aeris A300 Ai NO-DECO Card for your Reference and Share with your friends and buddies!

In No-Decompression Mode you may have Deep Stop prompt if Deep Stop option was set to ON before. In this case Aeris A300 Ai will display values related to Deep Stop function, like Stop Depth and Time, and Deep Stop icon (bar and arrows) and text message.

If you set Safety Stop function to ON – A300 Ai will prompt you displaying attributes for Safety Stop, like Safety Stop icon (bar and arrows) and text message, Stop Depth and Time counting down.

Switching gases is a simple procedure. It is accessible from Dive Main where you may choose the appropriate gas mix if it was enabled during setting up. Only thing to remember - dive computer will give an alarm, if PO2 selected gas goes to 1.6 ATA.

During the dive if we exceeded No-Decompression time and depth limits - Aeris A300 Ai would activate Decompression Mode – audio alarm will come up and 5 segments on TLBG, UP Arrows and alarm LED will flash.

After having that, you need to ascend safely to the required depth, shown on the display, or a bit deeper, and stay at that depth required time that is shown as well. When you complete required Decompression time, next shallower Stop Depth may be displayed, if needed, and you may ascend to that level to continue decompression process.

To assist us to complete decompression correctly, Aeris A300 Ai has main and alternative displays with all information we need. Below you may see the summary of Decompression Stop main and alternative displays:

Aeris A300 Ai DECO Card

Copy this Aeris A300 Ai DECO Card for your Reference and Share with your friends and buddies!


There are few Deco Violations that we may make unwillingly:

  1. Conditional Violation (CV);
  2. Delayed Violation 1 (DV1);
  3. Delayed Violation 2 (DV2);
  4. Delayed Violation 3 (DV3);
  5. Violation Gauge Mode (VGM)


Aeris A300 Ai manages those very well by giving us all data on displays and guide us through those conditions.

This Aeris computer constantly monitors PO2 and O2 conditions and upon reaching certain point it will give you High PO2 or High O2 alarms with all applicable dive data to help us stay in the safe side in those situations.


Aeris A300 Ai: Diving In GAUGE Mode

Dive computer may be set to Gauge mode. In this case Aeris A300 Ai won't compute No-Deco Limits and will work as a timer and depth gauge. You will be able to read tank pressure and access Compass mode.

Gauge Mode has its own set of menus with logs and history, no-fly time, op mode and set menu. Many items are shared with Air/Nitrox menus, except access to FO2 setings and other few things.

Below is the list of values displayed on main and alternative dive screens during diving in Gauge mode:

  • current depth;
  • Run Time;
  • Tank pressure;
  • Air Time Remaining (ATR);
  • VARI during ascent;
  • temperature;
  • current time


To make a Gauge Delayed Violation 3 (DV3), just out of curiosity, we need to descend below maximum operational depth for Gauge mode - 120 meters. At that moment dive computer will beep on you and LED and UP Arrows will flash.







After the Transition Period you will have access to following modes of Aeris A300 Ai:

  1. Plan Mode (Air and Nitrox Modes) and Pre Dive Planning Sequence (PDPS) at the range 9 - 57 meters – this function shows you for how long you may stay underwater safely and at what depth, according to your current nitrogen or oxygen accumulation, Algorithm selected, settings of Personal Conservative Factor and FO2, and 1st tank only counted;
  2. Time to Fly Countdown Timer;
  3. Desaturation Countdown Timer;
  4. Log Mode of Air, Nitrox, and Gauge Modes and it stores data of your 24 most recent dives (battery removal does not make any affect on Log memory); there are 3 pages of highly loaded dive data;
  5. History Mode Air, Nitrox, and Gauge Modes and it accumulates information, like number of dives, number of dive hours, and Max depth achieved from all your previous dives, lowest temperature recorded, longest dives (battery removal does not make any affect on History memory);
  6. PC interface – this function allows you to upload and download data to and from PC by using special cable and software







Aeris A300 Ai: What Divers Say


  • handy dual algorithm for conservative and liberal diving;
  • very convenient user interface with STEP BACK feature;
  • smooth switching between gas mixes...



  • user manual is a bit hard to follow;
  • could be made air-integrated for all tanks, not only for one;
  • high price for the unit...



After reviewing Aeris A300 Ai, we learnt that this new hose air-integrated device can be recommended dive computer as for beginners and technical divers too. Comprehensive set of features allows complete beginner starting dive career with very reliable buddy and progress faster, and technical divers will find 4 Nitrox gas-mix support and Dual Algorithm to accomodate all possible situations in diving.

Integrated digital compass is very handy addition to whole package. It is required to learn how to calibrate it first, but when everything is set up and running - it will always keep you on the right course. You need to play around with compass settings though to make it right!

Another thing to look at - side button. It is smaller than front buttons and it may be harder to press if you wear thick gloves.

Aeris A300 Ai dive computer
Aeris A300 AI
Dive-Computer-Wizard Rating
golden star golden star golden star golden star
half star


If you need reliable and advanced hose air-integrated dive computer with 4 gas mixes, Dual Algorithm for liberal and conservative diving, integrated digital compass, and you are ready to invest a bit higher price in your diving experience - Aeris A300 Ai is definitely worth your attention, as it continues the line solid and multifunctional Aeris computers!



Add comment
Jim Blaney, 14 October 2019 08:37
Compass ???

Playing with the DC while at the required 15 feet stop, I came across a compass. Once onboard and at home I tried to find the compass again, but been unsuccessful.

Also, have never been successful downloading my logbook either.

Bambie, 5 July 2013 11:53
Aeris A300 Ai Helped Me To Become A Tech Diver

I've been looking for a decent reviews for hose air-integrated dive computers and found it on this site. After comparing everything - I've bought Aeris A300 ai and never was sorry for that!

Great hose air-integrated dive computer. I learnt it very quick, thanks to my previous experience with dive computers. I've been diving with Aeris A300 ai for more than a year. I love its extensive number of functions and the way that this device pushes me to grow as a diver.

After having it for some time - I started diving with technical mixes and opened quite a few new experiences.

I can recommend A300 ai for divers who want to explore technical diving!

David, 3 March 2013 09:19
Very Sophisticated Hose Air-Integrated Dive Computer

I've bought Aeris A300 Ai at Leisure Pro following your recommendations and never was sorry for my decision!

I've logged 47 dives already and still exploring this instrument! Very reliable and intuitive computer. I do not worry about losing my wireless connection - all air data is steady on my display, which is well organized and easy to understand.

Aeris A300 Ai has broadened my diving experiences greately!

It took me a little time to get used to compass, I don't consider this a big deal!

I recommend this dive computer to anyone who may need advanced air-integrated instrument and don't mind having it on hose!

Robert, 15 November 2012 10:31
Aeris A300 Ai - Perfect For Technical & Advanced Recreational Diving, But Still Expensive

I've made 25 dives with Aeris A300 Ai dive computer, and can tell that I'm not disappointed with its performance. Handy Dual Algorithm feature gives me great advantage to dive with my buddies at the same profile without any problems.

I used only 2 gas mixtures so far and switching gases wasn't a pain. Even displays were easy to read in limited visibility and under low light conditions without using the backlight. I also found useful coloured bad graphs for TLBG and Ascent Speed. I need only glance at them to get full information. Digits are sharp and clear visible and alarms are loud enough even when I had hood.

I used Compass few times and think that this function wasn't worth to integrate into the main unit. I prefer using stand-alone diving compass. I can say that Aeris A300 Ai is very good dive computer, and cost every penny, even with its quite high price at these days market!

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