EIJKELKAMP Scuba User manual

Meet the difference
Nijverheidsstraat 9,
6987
EN Giesbeek, The Netherlands
T
[phone]
E
[e-mail]
I
royaleijkelkamp.com
© 2022-07 M-Scuba
Scuba and Scuba Trimeter water quality probes
This manual covers the Royal Eijkelkamp water quality probes Scuba and Scuba Trimeter.
For simplicity the term “Scuba” is used collectively for all models.
User manual

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Contents
About this manual.................................................................................................................................................................... 4
1. Learning the Scuba in 30 minutes ..................................................................................................................................... 4
1.1 See your Scuba..............................................................................................................................................4
1.2 Talk to your Scuba.........................................................................................................................................5
1.3 A short exercise.............................................................................................................................................7
2. Scuba basics ......................................................................................................................................... 8
2.1 Deployment specifications .............................................................................................................................8
2.2 Scuba control software flow chart ..................................................................................................................8
2.3 The Scuba has four basic applications .............................................................................................................8
2.4 Underwater cables ........................................................................................................................................9
2.5 Operating the Scuba with Eijkelkamp’s Amphibian 3 ........................................................................................9
2.6 What do the LED lights mean?........................................................................................................................9
2.7 The USB converter.......................................................................................................................................10
2.8 Accessories .................................................................................................................................................10
2.9 Flow cell .....................................................................................................................................................10
2.10 Routine maintenance ..................................................................................................................................10
3. The Scuba control software ....................................................................................................................................... 11
3.1 Scuba control software map.........................................................................................................................11
3.2 Home page .................................................................................................................................................12
3.3 Hot buttons ................................................................................................................................................13
3.4 “PC” pull-down menu ..................................................................................................................................14
3.5 “Scuba” pull-down menu .............................................................................................................................15
3.5.1 Manage Scuba files .................................................................................................................................................. 15
3.5.2 Logging setup ........................................................................................................................................................... 15
3.5.3 Calibration log.......................................................................................................................................................... 16
3.5.4 Sensors and parameters list..................................................................................................................................... 16
3.5.5 Calibrate................................................................................................................................................................... 17
3.5.6 Scuba version ........................................................................................................................................................... 17
3.5.7 Create a custom parameter..........................................................................................................................18
3.5.8 Delete a custom parameter ..................................................................................................................................... 18
3.6 Software updates........................................................................................................................................18
4. Sensors and calibrations ....................................................................................................................................... 19
4.1 The difference between sensors and parameters...........................................................................................19
4.2 Basics of parameter calibrations ...................................................................................................................19
4.3 Choosing calibration standards.....................................................................................................................20
4.4 Calibration record (“Cal Log”) .......................................................................................................................21
4.5 Sensor Response Factor (SRF).......................................................................................................................21
4.6 Temperature...............................................................................................................................................21
4.7 Dissolved oxygen.........................................................................................................................................21
4.8 Conductivity................................................................................................................................................23
4.9 pH..............................................................................................................................................................23
4.10 Reference electrode ....................................................................................................................................23
4.11 ORP............................................................................................................................................................24
4.12 Depth and vented depth (stage) ...................................................................................................................24
4.13 Turbidity.....................................................................................................................................................25
4.14 Fluorometers ..............................................................................................................................................26
4.15 Ion-Selective Electrodes (ISE’s) .....................................................................................................................27
4.16 Total Dissolved Gas (TDG) ............................................................................................................................28
4.17 PAR ............................................................................................................................................................28
4.18 Set barometric pressure and set time and date..............................................................................................29
5. Data logging ....................................................................................................................................... 30
5.1 What’s the difference between “Logging” and “Snapshot”? ...........................................................................30
5.2 Why we do logging the way we do................................................................................................................30
5.3 Sensor warm-up..........................................................................................................................................30
5.4 Setting up logging runs, logging file management, logging interval..................................................................30
5.5 Activating Scuba logging ..............................................................................................................................30
5.6 Am I using battery pack power or cable power?.............................................................................................31
5.7 Logging with an Internal Battery Pack ...........................................................................................................31
5.7.1 Changing IBP batteries in Scuba 50, 65, and Trimeters and activating logging ....................................................... 31

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5.7.2 Changing IBP batteries in Scuba 75 models and activating logging...................................................................32
5.7.3 Changing IBP batteries in Scuba 90 and 105 model and activating logging .......................................................33
5.8 Logging with an external battery pack...........................................................................................................33
5.8.1 The external battery pack ........................................................................................................................................ 33
5.8.2 Changing EBP batteries and activating logging ........................................................................................................ 34
5.8.3 Installing and removing the EBP .............................................................................................................................. 35
5.9 Batteries and battery life .............................................................................................................................36
5.10 Logging redundantly with telemetry .............................................................................................................36
5.11 Controlling sensor fouling ............................................................................................................................37
5.12 Protective cover ..........................................................................................................................................37
6. Small screen data displays ....................................................................................................................................... 38
6.1 Small-screen data displays ...........................................................................................................................38
6.2 Connecting the Amphibian 3 with a cable......................................................................................................38
6.3 Bluetooth battery........................................................................................................................................38
6.4 Establish Bluetooth communication..............................................................................................................38
6.4.1 Connecting the Amphibian 3 with Bluetooth for the first time ............................................................................... 38
6.4.2 Connect to “classic Bluetooth” Android data displays............................................................................................. 39
6.4.3 Connect to “Bluetooth Low-Energy” (BLE) data displays (including the IPhone) .................................................... 39
6.5 Example screens from small-screen data displays ..........................................................................................39
6.5.1 Screens Amphibian 3................................................................................................................................................ 39
6.5.2 Screens ScubaLink App............................................................................................................................................. 44
7. Frequently asked questions ....................................................................................................................................... 45
7.1 Our three most frequently asked questions...................................................................................................45
7.2 Sensors.......................................................................................................................................................45
7.3 Calibration and maintenance .......................................................................................................................47
7.4 Communication and software ......................................................................................................................49
7.5 Deployment and applications.......................................................................................................................49
7.6 General FAQ’s .............................................................................................................................................50
As this manual was written, these documents were on the flash drive next to the Scuba control software:
1M-Calibrating Ion-Selective Electrodes
2M-Calibrating the Scuba Turner fluorometers
3M-Cleaning pH sensors
4M-Eight ways to power a Scuba
5M-Field calibration crude oil sensor
6M-Four primary operating modes for Eijkelkamp multiprobes
7M-Scuba cable wiring
8M-Scuba integrated SDI-12 and MODBUS output operating instructions
9M-Scuba logging with uninterrupted external power supply
10 M-Scuba MODBUS communication protocol
11 M-Scuba RS-232 communications protocol
12 M-Scuba SDI-12 adapter
13 M-Standardizing Eijkelkamp’s Turner fluorometers
14 M-Warranty Scuba water quality probes
Do you need help?
Royal Eijkelkamp has the best customer service in the multiprobe market, so there’s no reason to get bogged down with
a problem. We welcome your call at [phone], or email at [e-mail]

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About this manual
If the text follows a mark (as shown on the left), this means that an important instruction follows.
If the text follows a mark (as shown on the left), this means that an important warning follows relating to
danger to the user or damage to the apparatus. The user is always responsible for its own personal protection.
Text Italic indicated text indicates that the text concerned appears in writing on the display or must be typed.
1. Learning the Scuba in 30 minutes
1.1 See your Scuba
1. The Scuba multiprobe is configured with your choice of sensors, and with or without a battery pack.
2. The underwater cable connects the Scuba to a data display (PC, Amphibian, logger, telemetry device
or, using the Bluetooth battery, a tablet or smart phone).
3. The storage/calibration cup protects the sensors when the Scuba is not in use (keep a few ounces of
tap water in the storage/calibration cup when the Scuba is not being used). And with the lid removed,
it holds your calibration solutions.
4. The Scuba flash drive contains the software for connecting your Scuba to your PC or other data
display, plus a digital copy of this manual, several instructional videos, and several technical notes.
5. The optional data cable lets you communicate conveniently with your Scuba when an underwater
cable is not needed, for instance, during calibration.
6. The USB adapter connects between your underwater cable (or data cable) and a USB port on your
display device. The USB adapter can also connect an external power supply to your Scuba if USB power
is not adequate (particularly with long underwater cables or large number of sensors).
Do not use the USB adapter with anything but a USB port and a Scuba.
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5
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7. The maintenance kit contains all the tools and maintenance items needed to keep your Scuba in top
shape.
8. The weighted sensor guard replaces the storage/calibration cup to protect the sensors during
deployment, and to help the Scuba sink.
1.2 Talk to your Scuba
Please follow the steps below to install the Scuba software on your PC or laptop (collectively, PC).
1Plug the Scuba flash drive into one of your PC’s USB ports.
2When the dialog box shown below opens, click Install Scuba software to upload the Scuba user interface software and
the USB driver software onto your PC.
Depending on which version of Windows you are accursed with, you might have to answer the usual questions about
your intention to load new software on your PC. Once you’re through with that, you’ll be returned to the same
screen that you started with, meaning that your Scuba software and USB driver are installed.
Click the Xin the upper right corner of the dialog box to close the installation process.
This software installation process should take only a few minutes.
Please call us ([phone]) if you have any problems.
Flash
drive

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Note that you can download the Scuba manual and various videos and technical documents that are stored on the
flash drive.
3If your Windows did not create on your desktop a shortcut to the Scuba control
software, and you would like to have one, click the Start button in the lower left of
your screen, click All Programs, click the Scuba folder, right-click “Scuba Control
Software”, and drag it to your desktop.
4Now connect your Scuba to the USB adapter using either a Scuba data cable or
underwater cable. Click the Scuba icon to connect your PC and Scuba. The home page will appear, showing the
Scuba’s real-time data and various menu options. You can close the program by clicking the Xin the upper right
corner.
If your Scuba does not connect with your PC, it may be that your organization’s network firewall
prevented the installation of the USB driver. Consult your IT department if you do not see the
Prolific USB driver listed in your device-driver menu (which is usually found in Settings after
clicking the Start button in the lower-left screen).

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1.3 A short exercise
Let’s do a quick exercise to show how easy the Scuba is to use. We will connect the instrument to a PC,
calibrate conductivity, and check the calibration log for the conductivity calibration information.
1Connect your Scuba to your PC with the USB adapter and either a data cable or underwater cable.
2Click the Scuba icon to launch the Scuba control software. Soon you will see the home page and the data
being sent from your Scuba.
3Fill the storage/calibration cup with tap water or conductivity standard and wait for the conductivity
reading to stabilize.
4Click the Scuba pull-down menu on the home page and click Calibrate, and then click SpCond on the next
screen.
5Type in the approximate conductivity of your tap water or the value of your conductivity standard and
click OK.
6Click on OK in the next screen to finalize the calibration and be returned to the home page. (D.5)
7Click the Scuba pull-down menu on the home page then click Cal Log on the next screen. At the bottom of
the list are the details of the calibration that you just did.
8Click on OK to return to the home page.
Was that easy, or what? Don’t you wish you had back all those frustrating, life-shortening, soul-crushing hours
you spent trying to decipher those other multiprobe manufacturers’ software?

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2. Scuba basics
Royal Eijkelkamp is the only major multiprobe manufacturer that provides a three-year warranty that covers all
sensors, including pH and DO.
2.1 Deployment specifications
The Scuba can be used in natural water up to 50 degrees C and 200 meters deep, except that ISE’s are rated to
10 meters deep, and TDG sensors and low-range depth should go no deeper than 25 meters.
2.2 Scuba control software flow chart
Please see the first page in Section 3.
2.3 The Scuba has four basic applications
1Manual data collection, also known as profiling, surveying, site-to-site measurements, etc., means that the
user is present at the monitoring site and uses a data display for observing measurements. This allows the
user to make data-based decisions in the field in real-time, and lets the user visit multiple monitoring sites
in one day. The data display can be a laptop, Amphibian, or almost any tablet or smartphone. The user
makes note of measurements either with pen and paper or, preferably, by using the Scuba’s snapshot or
automatic snapshot features. You might “snapshot” a series of measurements in one or more lakes or
streams during the day, and then download the data to your desktop PC that evening (see 3.3, 5.1).
2Unattended logging means that the user has set the multiprobe into its logging mode, deployed the
multiprobe in the proper location in the water, and then left the site. The Scuba can run for weeks at a
time with cable-supplied power or an optional Scuba integral battery pack. You can, for instance, set the
instrument to take a set of readings every half-hour, anchor it in an estuary, and return after two weeks to
retrieve the instrument and download the data to a PC, laptop, or Android device.
3Telemetry relay means that the user has connected the multiprobe to a telemetry device, deployed the
Scuba in the proper location in the water, and then left the site. A cable connects the multiprobe to the
telemetry system. The telemetry device uses satellite or cell-phone communication to periodically report
data collected by the multiprobe to the user’s office PC or to a proprietary web page. In many telemetry
systems, the user can also contact the multiprobe and request transmission of the most recent data.
Telemetry relay allows the user to collect data all night and all day for weeks without being present at the
monitoring site and allows the user remote access to those data at any time. Telemetry is helpful in
deciding when a trip to the field for multiprobe calibration or maintenance is necessary. Telemetry is also
ideal in locations for which access is dangerous or expensive.
On-line monitoring, also known as process-control monitoring, means that the multiprobe is connected to
a PLC, SCADA system, etc. An example is monitoring the input to a water-treatment plant for salinity or
chlorophyll. On-line monitoring allows the user to make water-quality-based decisions in real-time. The
Scuba is particularly effective in this application when more than one parameter is used in the control
loop.

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2.4 Underwater cables
The Scuba underwater cables have a RS 232 connector (left) and a female Scuba probe connector (right).
Vented underwater cables (VUC), which are used with the optional vented level sensor, have a small tube within the VUC
to connect the sensor to the surface of the water so that changes in barometric pressure do not affect level readings. That
vent tube is connected to a desiccant pack at the top of the VUC to prevent water from condensing inside the vent tube.
Later VUC’s are fixed to the Scuba and cannot be removed.
2.5 Operating the Scuba with Eijkelkamp’s Amphibian 3
(Please see 6.4.1 if you wish to connect to your Amphibian 3 via Bluetooth instead of a
cable.)
1Power on the Amphibian 3 data display.
2On the start-up screen, select “Amp_2_2_X” to launch the Scuba control software.
3Connect the Amphibian 3 to your Scuba cable’s 9-pin connector and turn the
Amphibian 3 on.
4You should see scrolling data from the Scuba's sensors.
The Scuba control software loaded on the Amphibian 3 mirrors the version for the PC with
some concessions for the small screen.
Section 5 has more information about small-screen data displays.
2.6 What do the LED lights mean?
The Scuba has three light-emitting diodes (LED’s), mounted on the circuit board visible through the instrument housing,
to help you understand what’s happening, and to provide information when troubleshooting a failure.
The green light blinks every second when receiving adequate operating voltage via the cable; it does not blink when the
Scuba operates under its own battery power.
The red light blinks five times upon power-up when logging is enabled.
The amber light blinks when the Scuba is receiving RS-232 communications from an external device (such as a PC or
logger).
A sequence of red and amber LED flashes tell you the voltage of your battery pack if you have activated logging. When
you first power-up your Scuba, the red LED will blink five times to indicate that logging is activated and to indicate the
first 3.5 volts of battery power, and then one amber blink for each volt, and one red blink for each half volt.
For instance, five reds, five ambers, and a red means 3.5 + 5 + 0.5 = 9 battery volts.

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2.7 The USB converter
Eijkelkamp’s USB converter converts your Scuba’s data stream to a USB port. Newer models have a power port on the
side that you can use to provide power to the Scuba if USB power is insufficient, or to protect your laptop’s battery. The
connector is fairly standard for power supplies, so you can plug in many third-party power supplies – but do not use a
power supply providing over 14 VDC.
If you are using a power supply that plugs into the wall, please use a GFI-equipped circuit.
2.8 Accessories
Eijkelkamp provides a number of accessories for the Scuba, including carrying cases, anti-fouling kits, SDI-12 converters,
data displays, telemetry systems, cable reels, etc.
2.9 Flow cell
If it is more convenient to bring the water to the Scuba than the Scuba to the water,
for instance when monitoring a ground-water well, you can simply screw a flow cell
onto the Scuba as you would normally screw on a sensor guard.
The flow cell cannot be used in combination with low flow pumping.
2.10 Routine maintenance
Clean your instrument periodically with warm soapy water. Liquid dishwashing soap
is fine. Do not use abrasives. Do not use acetone. Do not clean with gasoline,
kerosene, or industrial cleaners. Mild household cleaners work well. Clean sensor
stems with a soft brush.
Rinse well with tap water, and store sensors with tap water in the storage cup.
Replace any o-rings with visible cracks. Keep o-rings greased with silicon grease
(found in your maintenance kit). Always remove batteries and clean your Scuba
prior to storing it for prolonged periods.

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3. The Scuba control software
3.1 Scuba control software map

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3.2 Home page
We call the Scuba control software’s home page the “home page” because you can access all the Scuba functions from
this screen. The home page functions are:
These two
buttons are pull
down menus
These eight buttons are “hot
buttons”; short-cuts to important
and often-used functions
This area is continuously updating,
real-time data from your Scuba.
The bottom line of the screen
tabulates some information you
might find handy.
The line of data highlighted in
yellow is the most recent line of
data sent from the Scuba.

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3.3 Hot buttons
“Hot buttons” are the little squares you can click on to do something important without leaving the home page. The hot
buttons are:
1Click the “Scuba logging is OFF” (or, “Scuba logging is ON”) hot button to enable or disable the Scuba’s
logging function. It lets you tell the Scuba that you will be deploying it in the field for unattended logging.
Clicking the hot button toggles the logging on and off. Generally, logging should be off – turn logging to
ON only when you’re preparing for unattended deployment.
2Click the “Circulator is Off” hot button to toggle your circulator, if any, on and off.
3Click the “Wipe one cycle now” hot button to activate one cycle of the turbidity sensor’s wiper. If your
Scuba doesn’t have turbidity, you can still click this button, but nothing will happen.
4Click the “Clear screen” hot button to remove the data you see on the screen and start over with only the most
recent data. Clicking this button does not close the program.
5Click the “Capture one line of data to PC with annotation” hot button to save the most recent line of data
(as shown in the yellow band on the home page) to your snapshot file, along with a brief note that you
might wish to append to the data. Type that note in the annotation box. The note will be saved, along with
the data, in your snapshot file. (see 3.3.2)
6Click the “Capture one line of data to PC without annotation” hot button to save the most recent line of
data (as shown in the yellow band on the home page) in your snapshot file. (see 3.3.2)
If this button says
“ON” click on it to
turn Scuba logging
“OFF”, click on it to
turn Scuba logging on.
Click this button to
toggle your circulator,
if any, on and off.
Click this button to
start one wipe cycle
for your turbidity
sensor, if any.
Click on this button to
clear the data area.
When you click on this
button, a comment
screen appears (see
below), and then one
frame of data is sent
to your PC snapshot
file (along with the
comment you typed
in the box). The
comment is called an
annotation.
Click on this button to
send one frame of
data to your PC
snapshot file without
an annotation.
Click this button to list
available Bluetooth
Scubas.
Click this button to
rebuild the data in
this screen

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7Click the “List Bluetooth Scubas” hot button to show a list of available Bluetooth Scubas.
8Click the “Restart” hot button, data will be rebuild on the screen.
3.4 “PC” pull-down menu
The Scuba has two pull-down menus, called PC and Scuba. They’re called pull-downs because when you click on them, a
bunch of hidden buttons appear. When you click on the “PC” pull-down menu, you get six buttons to choose from:
1Click Set Scroll Interval if you wish to change the time for which lines of data on your data display screen
are updated. You can click on a specific scroll interval or type in your own.
2Click Set Snapshot Location if you wish to specify the file in which your snapshots are to be filed. This calls
up the standard “Save As” (or equivalent) function of your data display’s operating system. Follow the
instructions just as if you were saving, for instance, a new Word document.
A “Snapshot” is what happens when you choose to log, or store, one line of data. That line can be
representative of, say, stabilized readings at 10 meters in a particular lake, or any other line of data you
find interesting. (3.4, 5.1)
If you want to find those interesting lines of data later, it’s a good idea to put them in a file whose location
you can actually remember.
Notice that the active snapshot file location is listed on the bottom line of the home page.
3Click Automatic Snapshot if you wish log data automatically and quickly, for instance to catch a transient
situation or if you are rapidly profiling a column of water. You can also use Automatic Snapshot to save
data while you go to lunch. The data are stored in the snapshot file as determined by “Set Snapshot
Location”. (3.4, 5.1)
In Automatic Snapshot, data are logged at the same interval as they are displayed on your data display
screen when you’re not in Automatic Snapshot. For instance, if you have set your PC scroll interval to 10
seconds, automatic snapshot will record data at 10-second intervals.
4Click Graphing to see your Scuba real-time data in graphical form. The graph view is helpful when profiling
to watch for sensor stability. For example, dissolved oxygen readings are temperature and salinity
corrected, so when the probe goes through water with thermal or saline stratification, it’s important to
wait for stable readings before recording a snapshot.
5Click COM Ports to change the USB port that your Scuba control software uses to talk to your Scuba.
Normally the Scuba control software searches all active USB ports until it finds a Scuba to talk to, and
then it stops looking. But you might have more than one Scuba connected to your PC at one time, for
instance if you are calibrating several Scuba’s at the same time or are using your PC to monitor several

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Scuba’s at the same time (like in a fish hatchery with multiple tanks). In that case, you can click COM
Ports to see the list all the COM ports that your PC knows about and choose another COM port
corresponding to another for the Scuba.
6Click Control Software Version to get a screen that tells you the software version that your data display is
using to talk to your Scuba.
3.5 “Scuba” pull-down menu
The Scuba has two pull-down menus, called PC and Scuba. They’re called pull-downs because when you click on them, a
bunch of hidden buttons appear. When you click on the “Scuba” pull-down menu, you get eight buttons to choose from:
3.5.1 Manage Scuba files
Click on Manage Scuba Files to see the names of all the data files
that are stored in your Scuba. Highlight the file you’re interested
in by clicking on it. Then, with the other buttons on the screen,
you can then view that file on your data display screen, delete
that file, or export it to your data display (via the Save As function
standard to Windows).
You may highlight multiple files to select for export.
3.5.2 Logging setup
All Scubas include data memory and software that automatically logs
(stores) a line of data any time you want. The logging set-up screen lets
you change the instructions the Scuba will follow when logging. You can
click on your preferred logging interval. You can also select to append
any new data to a file that already exists in the Scuba by clicking
“Browse Scuba”, then selecting a file and clicking on “OK”, or you can
create a new Scuba logging file by typing the new file name under “Log
File Name”.
For your convenience, the active logging file name is displayed in the
bottom line of the home page.

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3.5.3 Calibration log
Click on the Cal Log button to see, you guessed it, the calibration record. This is a lifetime, permanent record of all
calibration changes for your Scuba (4.4).
3.5.4 Sensors and parameters list
Click on the Sensors and parameters list button enables the parameters listed by clicking the box (to the left of the
parameter name) to produce the check mark. Clicking on a box with a check mark removes the check mark and disables
that parameter.
Note that if you enable a parameter but don’t have a sensor for that parameter, it would be a huge coincidence if the
data were accurate.
The order of the enabled parameters in this list is the order in which the parameters will appear in your data display
home page, the order in which they will appear in logging files, and the order in which they will appear in snapshot files.
You can change the parameter order by clicking on (i.e. highlighting) the parameter name and then moving the
highlighted name up or down by clicking on the up- and down-arrows at the bottom of the screen.

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3.5.5 Calibrate
Click on the Calibrate button in the Scuba pull-down menu to get a screen listing all the parameters that can be calibrated
in a Scuba. Click on the parameter you wish to calibrate to see its calibrate screen. This screen has calibration instructions
for the specific parameter and shows the current reading for that parameter.
If your calibration requires a calibration standard, type your calibration standard value where it says “enter calibration
value”. When the parameter reading has stabilized in the calibration solution, click on the OK button. If your calibration
has an acceptable SRF (Sensor Response Factor, an indication of the sensor condition (4.4); the calibration will be
accepted, and you will be returned to the home page. If you click on “OK”, the calibration will be accepted despite a
deviant SRF, and you will be returned to the home page). If you click on “Cancel”, you’ll go back to the calibrate screen.
How do I know if I need to calibrate?
The simple answer is that frequent calibration will give you better data. The more meticulous you are
with calibration, the better data you will gather. If you are uncertain whether you need to calibrate, check your
sensors against a known sample. If the reading is within the accuracy specification and/or your accuracy
expectations, there is no need to calibrate.
Experience and your program’s accuracy expectations will help determine calibration frequency for the various
sensors. If, for instance, your reservoir discharge is hovering near the regulatory minimum for dissolved
oxygen, you should pay special attention to DO calibration frequency and technique. On the other hand, if a
conductivity accuracy of +/- 10% is OK, you needn’t calibrate conductivity very often.
3.5.6 Scuba version
Click this button to see the version number for the software that your Scuba uses.

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3.5.7 Create a custom parameter
Suppose you determined the relationship, specific to your waters, between
conductivity and total dissolved solids (TDS). Or suppose you had an algorithm
relating water level to flow for a certain site. With the Scuba, you can create new
parameters – call them, for instance, My TDS and Site 4b Flow – that will show up on
your home page and logged data just like temperature, pH, and all the other
parameters.
To make this happen, click on the Scuba pull-down menu, and click on Create
Custom Parameter. Follow the instructions to name your new parameter, specify
the units that you wish the new parameter reported in (e.g. mg/l for TDS), and
tell the Scuba how to calculate your new parameter (using mathematical
operators as you would in Excel).
Note: Enclose the entire expression in parentheses. After creating or deleting a
parameter, restart your CPU. Custom parameters cannot be created with the
Amphibian2 Scuba control software.
3.5.8 Delete a custom parameter
Suppose you’re having second thoughts about the customer parameter you created. Click on the Scuba pull-down menu
and click on Delete Custom Parameter. Follow the instructions.
3.6 Software updates
A new Scuba software version (2.2.10), was implemented. The new software makes the following improvements to the
turbidity parameter:
1) The Sensors and Parameters List now contains the parameter “Turb_FNU”, which replaces “Turb NTU”.
Turb_FNU is the same measurement as Turb NTU, except altered slightly to make its true ISO 2027 response
linear with formazin.
2) The Sensors and Parameters List now contains the parameter “Turb_Mod”, which is the same measurement as
Turb_FNU, except NOT altered to make its response linear with formazin. It is numerically equal to the earlier
parameter Turb NTU.
3) The Sensors and Parameters List now contains the parameter “Turb_NTU”. Turb_NTU is the same measurement
as Turb_FNU, except with units of NTU instead of FNU if you prefer that your data are labeled NTU. Calibrating
Turb_NTU also calibrates Turb_FNU, and vice-versa.
4) The Sensors and Parameters List now contains the parameter “Turb2_FNU”. Turb2_FNU is the same
measurement as Turb_FNU (or Turb_NTU, if you prefer NTU’s), except multiplied by a Turbidity scale factor.
Turb2_FNU is a unique parameter that helps you match Eijkelkamp turbidity readings with readings from other
types of turbidity sensors for the sake of data continuity.
For instance, suppose you found that an Eijkelkamp turbidity sensor read 89 while another turbidity sensor read
78 in the same sample. The Turbidity Scale Factor is 78/89 = 0.88. You can type that Turbidity Scale Factor into
the Scuba when calibrating Turb2_FNU. Thereafter, all Turb2_FNU readings will be the Eijkelkamp turbidity
readings multiplied by 0.88 to mimic the readings that you would get with the other turbidity sensor.
The software specific to turbidity has changed as well.
In most cases, you can update your Scuba’s software with these new software if you wish to take advantage of the new
features dealing with turbidity.

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4. Sensors and calibrations
4.1 The difference between sensors and parameters
A sensor is a basic element, like a thermistor or a pH glass electrode. Each sensor has one or more parameters. For instance, we
use a thermistor to measure both temperature °F and temperature °C – that’s one sensor with two parameters. A conductivity
sensor can be read as specific conductance μS/cm, specific conductance mS/cm, total dissolved solids mg/l, and salinity (PSS) –
that’s one sensor with four parameters.
4.2 Basics of parameter calibrations
The Scuba never guesses parameter values, so you have to calibrate it from time to time by simply telling the instrument
what it should read in a calibration situation for which the correct parameter value is known. Here’s the general
procedure; instructions for specific parameters will follow beginning with 4.5:
1Clean the sensor and perform any necessary sensor-specific maintenance.
2Select a calibration standard whose value is close to the values you expect to see in the field. For best
results, use fresh calibration solutions, and discard once they have been used.
3Rinse sensors thoroughly (more than once may be required) with DI (deionized) water, especially if you
have been using other calibration solutions. Pour the water into the calibration cup, position the
“stopper” side of the lid on top and shake the Scuba vigorously to remove traces of old calibration
solutions – repeat if necessary.
4Rinse the sensors twice with a small quantity of your calibration standard. Discard the used calibration
standard.
5Immerse the sensor in the calibration standard. This is usually accomplished by pouring the standard into
the Scuba’s calibration cup once it has been screwed onto the Scuba housing. Secure your Scuba with the
sensors pointing up and fill the calibration cup with your calibration standard. Make sure the standard
covers the sensor entirely, and that it also covers the thermistor for those parameters that are
temperature-compensated. For turbidity sensors and other fluorometers fill the cup to at least 1 ½ inches
above the sensor’s lens surface.
Select the parameter to be calibrated by clicking on the Scuba pull-down menu in the home page, then
clicking on Calibrate, and then clicking on the parameter you wish to calibrate. First, enter the calibration
value and press enter; when the reading has stabilized, press enter to calibrate. The Scuba will report the
resulting Sensor Response Factor (SRF); then press Yto accept the calibration, Nto back up one step, or
Exit to leave the sensor uncalibrated. (3.5.5)

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4.3 Choosing calibration standards
For best results, choose a calibration standard whose value is close to what you expect to see in the field. For
example, calibrate with a 1413 μS/cm specific conductance standard if you expect to see specific conductance
readings between 500 and 1000 μS/cm in the field. Calibrating with a sea water standard or a very low
standard would not be appropriate in that case. Similarly, if your waters tend toward the acidic, calibrate with
a 4-buffer instead of a 10-buffer.
If you are moving your multiprobe across wide ranges of water conditions, you may wish to recalibrate to
match the new situations. For instance, if you are measuring a clear lake during the morning and a high-
sediment stream in the afternoon, you might consider recalibrating at noon with a high-range turbidity
standard.
The table below shows common calibration practices.
Sensor Standard method of calibration Available calibration solutions Comments
Temperature never requires calibrating N/A
pH / pH reference 2 or 3 points pH 4, pH 7, pH 10 pH 7, pH 10 most common
ORP 1 point ORP Standard 200 mV
Conductivity 1 point CD Standard, 0.5 Molar, 58670 Micro S
CD Standard, 0.1 Molar, 12856 Micro S
CD Standard, 0.01 Molar, 1412 Micro S
CD Standard, 0.001 Molar,147 Micro S
brackish/saltwater borderline
brackish typical freshwater very
pure fresh/glacial
Reference Electrode calibration not required N/A replace pH electrolyte solution
at routine calibration
Depth adjust for barometric pressure N/A recalibrate at deployment site
for best accuracy
Turbidity 2 points 0 NTU, 10 NTU, 100 NTU, 400 NTU calibrate near expected value
HDO (Optical DO) calibrate at 100% saturated
water
DI water -shake vigorously to
oxygenate
set BP before calibrating, recal
at deployment site for best
accuracy
Chlorophyll 2 points secondary solid or 40µg/L solution
or lab sample
Rhodamine 2 points secondary solid standard or
rhodamine
Blue Green Algae 2 points secondary solid standard or lab
sample
Ammonium (NH4+) 2 points Lo 4.63 mg/l; Hi 46.3 mg/l
Nitrate (NO3+) 2 points Lo 4.62 mg/l; Hi 46.2 mg/l
Chloride (CL-) 2 points CD Standard 147 Micro S
CD Standard 1412 Micro S
enter 34.3 during calibration for
low
enter 319.3 mg/l for high