ourselves entering the ‘dog days’ of summer as temperatures soar
and algae bloom. It is during this time of the year that those of
you who are constantly on the look out for blooms should consider
how a chlorophyll monitoring system could help you. Systems such
as the AlgaeWatch
On-Line Fluorometer have been designed to assist you in avoiding
algal bloom issues by providing sensitive and accurate real-time
data on the algal growth in any water body. The availability of
real-time data will allow you to track diurnal changes as well as
longer trends in algal biomass.
If you are involved
in water resources, you will be able to witness the onset of a bloom
and take appropriate action before it reaches damaging levels. Additionally,
the data will enable you to make efficient use of treatment chemicals,
utilize the best possible water source, investigate the potential
presence of taste and odor causing species, and predict filter rates.
For those of you interested in monitoring coastal areas, bays or
lakes, real-time algal biomass data can provide an informative data
set to an existing monitoring program, detect the potential presence
of harmful algal blooms, and provide a measure of the effectivity
of algal treatment. We are committed to offering you simplified
solutions for difficult monitoring problems.
See the article: "Simplifying
Fluorometer Calibration" for information on the products
and services available from Turner Designs that will ensure you
collect valid data - in the lab, or in the field. Plus, our new
e-support for chlorophyll a measurements section of our web
site is designed to provide the background and step-by-step instruction
to transform anyone into a chlorophyll monitoring expert!
Are you interested in monitoring Cyanobacteria? We would like to
hear from you, and in appreciation for your responses, we'll send
you a Starbucks card for completing our cyanobacteria
And of course, if you
still want to speak to someone, we're here to help. For sales assistance
or quotes please call our sales team at (408)212-4017 and for technical
assistance please call our technical support team at (408) 212 4016.
We look forward to hearing from you.
Director of Sales and Marketing
August will be the last month to take advantage of our AlgaeWatch
Fluorescence Solutions in the Palm of your Hand
AquaFluor Handheld Fluorometer provides affordable fluorescence
solutions for those that need a lightweight and easy-to-use fluorometer
out in the field. This dual channel instrument comes in the following
In Vivo Chlorophyll a & Turbidity (8000-001)
· Rhodamine WT & Turbidity
· Extracted Chlorophyll a &
Measurements for the first two models
are taken by discrete sampling with 10mm x 10mm cuvettes, while
the 8000-007 model utilizes 12mm test tubes. The intuitive push
button layout of the AquaFluor makes this unit very easy to use,
while the rugged waterproof design makes it hard to abuse. For more
detailed specifications on this instrument, please view our AquaFluor
First introduced in 2000, our handheld
fluorometers have been meeting the fluorescence needs of thousands
of customers throughout the world. Universities, research institutions,
and environmental consultants are among the customers that have
benefited from the use of our handheld fluorometer with their research
projects. A few example customers that utilize the AquaFluor Handheld
Fluorometer for their research includes:
University of Arizona - Water Resources Department(chlorophyll/turbidity)
· USGS - Menlo Park, CA - Water
Resources Department (rhodamine dye/turbidity)
· Moss Landing Marine Labs (chlorophyll/turbidity)
· University of Connecticut
- Marine Science Department (chlorophyll/turbidity)
· Malcolm Pirnie - Environmental
· USGS - Tampa, FL (rhodamine
· Smithsonian Institution Marine
· GE Betz (chlorophyll/turbidity)
· USGS - Ann Arbor, MI (chlorophyll/turbidity)
· University of Maryland - Horn
Point Lab (chlorophyll/turbidity)
· USGS - Moundsview, MN (rhodamine
· Naval Research Laboratory
- Stennis Space Center, MS (chlorophyll/turbidity)
· JC Headwaters, Inc. - Environmental
· US EPA - Philadelphia, PA
· University of Texas at Austin
- Marine Science Department (chlorophyll/turbidity)
· USGS - Rolla, MO (chlorophyll/turbidity)
· US EPA - Port Orchard, WA
· Southern Ute Indian Tribe
- Ignacio, CO (extracted chlorophyll/ammonium)
To learn more about how the AquaFluor
can assist you with your research, please don't hesitate to contact
| Jim McCormick, our Tech Support Manager, has been with Turner
Designs for over 15 years and has extensive expertise with our entire
line of instruments.
"Jim's Corner" will feature common questions that provide a better
understanding of the operation of our units. Send your technical question
to Jim by clicking here
We plan to use your Model 10-AU Fluorometer
to perform a mixing and dispersion study using Rhodamine WT dye
at a wastewater plant that discharges into a river. What is the
best way to store and retrieve the 10-AU data as we perform continuous
flow through monitoring on transects in a small boat?
The 10-AU allows you to capture data
several ways. The most popular way is to use the Internal Data Logging
option, if your 10-AU has this option installed. The second way
is to use the Serial Data output from the 10-AU connected to a computer
running a Data Acquisition (DA) program. The HyperTerminal program
that is included with the Windows operating system will capture
serial data, but may limit the total time data can be saved continuously
in a file. Another DA software program is made by Windmill Software
Ltd. and they offer some versions free of charge. For more information
please visit their website.
The Windmill SW can also allow the capture of GPS data to correlate
position to the 10-AU readings.
The third way to collect data is to
use the Analog output of the 10-AU connected to an external datalogger.
Refer to Appendix 11 of the 10-AU User Manual for more details.
"How often should I calibrate
"How can I tell if my fluorometer needs re-calibrating?"
Turner Designs has significantly simplified
the calibration process as well as the process of validating whether
a re-calibration is required. To determine if a calibration is required,
Turner Designs has developed a series of secondary standards. Use
of these standards eliminates the need for primary standards (a
pure solution that has a known concentration) since, once a relationship
is established, the solid standard simulates a concentration of
the primary fluorophore being measured.
This secondary standard is much simpler to use because it has the
advantage of being instantly ready for use, and it is easy to transport
and store. Plus it is essentially independent of other environmental
variables such as temperature. However, it is a secondary standard
because it is not of the same substance as is being measured, (normally
chlorophyll, or a tracer dye), and can only be used in place of
a primary standard if it has previously been correlated with a primary
Turner Designs also sells Primary Standards
for calibrating fluorometers when making extracted chlorophyll measurements.
With the emphasis again on ease of use, the liquid Chlorophyll standard
is supplied in an ampule ready to use, and comes with a certified
concentration, and certificate of analysis.
When performing in-vivo sampling, using
Solid Secondary standards is the most logical approach for calibrating.
Then when you extract samples you will determine the correlation
of the Secondary Solid standard for a given "in-vivo"
Chlor a concentration, visit our website
for more details.
Likewise, when you perform extracted
chlorophyll analysis, initially you will calibrate with a Primary
Standard in the appropriate solvent, and at that point will determine
the correlation of the Solid Secondary standard on a freshly calibrated
This gives you the convenience and
cost savings of using the Solid Secondary standard on a routine
basis for doing your Calibrations for both the in-vivo and extracted
Chlor measurements, so that you can calibrate for either situation
quickly and repeatedly.
To obtain further information on Turner
Designs Primary and Secondary Standards please visit our website,
or email our support
Falls Laboratory Utilizes 10AU & SCUFA for Hydraulic Experiments
The St. Anthony
Falls Laboratory (SAFL) is a teaching and research facility of the
Department of Civil Engineering, University of Minnesota. Their
goal is to advance the knowledge and understanding of environmental
hydraulics, turbulence, earthscape evolution, and climate/ecosystem
dynamics via high quality experimental, theoretical and computational
research. As a group, they are committed to transferring that knowledge
to the engineering community and to the public through applied research
and outreach activities.
Ben Erickson is one of the scientists
at SAFL, and is considered the "fluorometer guru" of the
laboratory due to his extensive experience with the Turner Designs
line of fluorometers. Ben and his colleagues utilize the 10AU and
SCUFA fluorometers to conduct hydraulic experiments using rhodamine
WT dye as a fluorescent tracer. The information learned in their
dye tracing experiments is then applied to solving real life hydraulic
One of the recent issues that the SAFL
is currently working on is the feasibility of an emergency sewage
storage system for overflows caused by above average amounts of
rain runoff in an urban location. To investigate the feasibility,
Ben and his team conducted experiments on a smaller scale system
that resembled the location under investigation. The key questions
that required the use of our fluorometers was how to best set up
an aeration system for sewage treatment. The fluorometers were used
to quantify diffusion and dispersion in and around a deep bubble
To investigate the aeration set-up,
the SAFL placed submersible aerators at strategically placed locations
on the bottom of the experimental water system. Slugs of rhodamine
WT tracer dye were then released at the bottom of the system, while
the 10AU and SCUFA Fluorometers monitored its concentration at various
points in the water column. With the data from multiple trials,
estimates were made on the rate that a bubble column would entrain
the surrounding water.
To address the gas exchange questions,
the experiment took the data from the previous entrainment experiments
and decided on a reasonable flow rate to inject of the test solution.
Known flow rates of the conservative tracer rhodamine WT and a volatile
tracer were then added at the bottom of the water column. Once at
a steady state, water samples were collected and analyzed utilizing
fluorometers and gas chromatography yielded data indicating how
much tracer gas escaped from solution into gas. The flourometers
were used both in the final analysis and during the course of the
experiments. They proved quite valuable by allowing the researchers
to look at the real time data as the experiment progressed.
With the amount of useful data generated
from these experiments and the fluorometers, Ben considers the research
project to be an overall success. This information will soon be
transferred to the engineering community to enable them to make
sound decisions on the emergency sewage storage system project.
To learn more about the exciting research that goes on at SAFL,
please be sure to visit their website.
It All Adds Up...
is a series of articles for people
who want to obtain the best possible results from their fluorometer.
month Technically Speaking described how to improve measurement
repeatability by determining and implementing a cleaning schedule
for the sample cell.. This month's article will describe how ambient
light affects fluorescence when measuring in vivo chlorophyll, and
how to compensate for it.
Effect of Light
on in vivo Chlorophyll Fluorescence
Light history, (the amount and type of light environment of
a particular environment preceding an in vivo fluorescence measurement),
can have significant effects on the fluorescence in living algal
cells. At low light levels, algal cells can optimize the light
uptake by pushing chloroplasts to the outer edge of the cell
and/or by producing more chlorophyll per cell. At high light
levels ,near the surface, non-photochemical quenching can result
in a decrease in fluorescence. Both of these responses can alter
the in vivo fluorescence signal without a corresponding change
in the algal biomass.
In Figure 1, the bottom of the photic zone (lit zone of the
ocean) is characterized by very low light levels. This
results in a lower level of fluorescence due to low algal
biomass. However, the fluorescence:biomass ratio may be
higher in the darker zones due
to the cells acclimation to the ambient light field.
|In Figure 2, higher
in the photic zone the cell growth is still inhibited by
lower than optimal light but fluorescence:biomass may remain
high and algal biomass is increasing.
|Figure 3 depicts an
optimal environment for growth with sufficient levels of light
and nutrients. In vivo fluorescence will most accurately measure
algal biomass in this environment due to the lack of low or
high light effects on fluorescence.
Figure 4: Near the surface
with high levels of solar radiation, non-photochemical
quenching can often inhibit the fluorescence. This phenomenon
occurs when there is too much light for the algal cells
to process. This state causes a decrease (quenching) of
the fluorescent signal that is un-related to the photosynthetic
rate or algal biomass.
Two steps that can be
taken to avoid false chlorophyll readings are:
· Conduct profiles at night
· When using a flow-through fluorometer, use an opaque
hose when sampling natural waters. (The transport time of the water
in the hose will dark adapt cells to an extent, reducing light history
For more information on environmental factors that can impact in
vivo chlorophyll measurements, please visit the Turner
Designs e-support pages.
Next month's article will explain why
the Calibration Solution reading may change immediately after calibrating