Over recent times we have noticed an increasing amount of media coverage and industry chatter regarding the role of light in aquaculture. Most of this has been in relation to the use of low-energy technology to reduce costs, and in this area almost all the talk is about LED

1. FISH FARMING TECHNOLOGY
Light Emitting Diode (LED) Lighting systems for early stage aquaculture
L
ight Emitting Diode (LED) technology has proven itself in almost every
environment where artificial lighting is deployed, and the various agricultural
sectors involved in intensive food production are no exception.
Fixture longevity and significant reductions in energy consumption have seen
LEDs becoming increasingly common. Less widely publicised, however, is the
notion that emerging lighting technology may offer the aquaculture industry more
than simply a way to reduce operating costs….
Commercial horticulture has long recognised the critical role of light in
influencing product quality and yield. Growers and their suppliers moved quickly
to adapt LED technology to deliver
the precise spectral and intensity
values needed to dramatically improve
production outcomes, effectively
“doubling up” any cost-reduction
benefits that the new technology
brought.
Now, a UK-based company has
developed a lighting system to deliver
the same benefits to fish farmers.
Tropical Marine Centre (TMC) is best
known in aquaculture circles as “TMC
Commercial” for their recirculation
filtration systems, which are widely
used by hatcheries around the world.
Over the last seven years, they have
also been developing LED lighting
systems for aquatic applications,
and extensive research and multiple
trials have led to the launch of a new
commercial lighting brand - BioLumen
Lighting Solutions.
We spoke to Gyles Westcott, part of
the lighting development team at TMC,
to get more information about the range.
“Hatchery managers have always
known that light is important – indeed,
photoperiod and light intensity are part
of every production protocol.
“However, light is more than just two
basic variables! In fact, for some time
now, biologists have understood that the
very specific photic conditions of the
aquatic environment are active, biological drivers, particularly in the early-stages of development.
“To complicate matters further, these photic drivers are highly variable across different species, across
the different life-stages of those different species, and across the diverse range of biotopes that they might
occupy as they develop.
“So, the conditions under which salmon eggs incubate are vastly different to the conditions under which,
for example, Sea Bass eggs incubate. All of this is quite obvious, yet fish farmers have never had a fully
developed system allowing light conditions to track the changing requirements of the chosen culture species.
The reason for this is that previously, there has never been an economically viable technological solution to
delivering such a complex photic solution.
Over recent times
we have noticed an
increasing amount
of media coverage
and industry chatter
regarding the role of
light in aquaculture.
Most of this has been
in relation to the
use of low-energy
technology to reduce
costs, and in this
area almost all the
talk is about LED.
46 | January | February 2016 - International Aquafeed

2. FISH FARMING TECHNOLOGY
“Of course LED changed all this, and it is now possible
to deliver a precise and cost-effective solution to almost
any lighting specification. In the case of BioLumen,
this has enabled the development of a modular, fully
controllable, flexible and easy-to-install, low-energy
platform which delivers biologically optimised lighting,
according to the specific needs of a culture species, at
any stage of development.”
The key question is, of course, can a change in lighting
actually have a positive effect under commercial
conditions, and if so, is any uplift enough to warrant the
cost and effort involved? The general shift towards LED
would indicate that businesses that make the change
would benefit simply by reducing their energy footprint,
but is there more to gain than simply cost savings?
“Many would argue that any gains would be marginal
at best” Gyles conceded, “but then marginal gains,
especially in a hyper-competitive and high-risk
environment such as early-stage aquaculture, can be
the difference between a simply viable yield, and an
exceptional yield!
“A recent case-study we worked on, for example, cited
a 1% uplift in survival across each stage of a single
cycle of Sea Bass production, through to harvest, as
the benchmark required to justify a lighting re-fit of the
trial site. The numbers are clearly different for different
species, but in this instance, the resulting uplift in bio-
mass at harvest amounted to more than 30 tons!”
Of course, any industry professional will know just how
complex a successful culture protocol can be and many
people will not appreciate the addition of yet another
environmental variable that would need to be defined and
then actively managed. But in the case of lighting, this
may be easier than expected to achieve.
“As previously mentioned, intensity and photoperiod
values are already part of every established hatchery
protocol. What TMC is providing is a simple interface
that allows these variables to be precisely defined, using
light that has been spectrally optimised to match what
we know about the photic conditions which the culture
species requires”.
In terms of benefits, it is still early days, but results
from ongoing trials paint a positive picture.
“There is a great deal to be up-beat about”, he
continued. “Shorter incubation times; more synchronous
hatching, with fewer deformities; faster yolk absorption
and earlier metamorphosis; faster growth; dramatic
reductions in trauma and mortality associated with
“light shock” – these are just a few of the benefits being
reported in trials on commercially important species
such as Sea Bass, Turbot, Perch, Sea Bream and Senegal
Sole”.
He then went on to explain the system in
more detail.
“The BioLumen System comprises four
distinct elements. The first of these is our
range of AquaRay and Ecoxotic light fixtures.
These range in power from around 14watts
to the largest Ecoxotic Cannon which is
160watts. More importantly, the spectral
profile of each model is precisely defined,
and this allows us to combine different
elements from the range to precisely match the
prevailing spectral characteristics of almost
any aquatic zone.
“A key component in several models is our
industry-patented “Nature Perfect” diode.
This is effectively a 465nm blue diode which
has been “white shifted” to produce a peak at
around 540nm, an element of the spectrum that
is dominant in a wide range of aquatic nursery
zones. These include estuaries, inshore coastal
areas and the oceanic surface zone where the
eggs of so many pelagic species incubate.
“The second and third elements of the system
are a range of addressable digital drivers,
in IP66 enclosures, and a flexible system of
connectors and mounting accessories that
allow either turn-key or phased installation
to be done quickly and easily, with very little
alteration to new or existing infrastructure”.
“And lastly, the most important element,
which is our BioLumen Controller. This
is the real brains of the system, providing
dramatically enhanced lighting control via a simple,
networked user interface”.
This Controller allows users to select from a number of
setting profiles, the first of these being “solar.” For this
system the user is able to specify the latitude/longitude
values of a desired location. The system then matches
the photoperiod values for that location, including
sunrise, sunset and the seasonal shift in noon intensity,
relative to winter and summer solstice.
Image: Light
Emitting Diode
(LED) technology
has proven itself
in almost every
environment where
artificial lighting is
deployed, and the
various agricultural
sectors involved
in intensive food
production are no
exception.
International Aquafeed - January | February 2016 | 47

3. FISH FARMING TECHNOLOGY
The next profile that is available is the “Simple”
setting. For this profile the user defines a fixed set of
values (sunrise, sunset, dim-up duration and maximum
output) to apply each day.
The third and final profile that is available is
referred to by the name “manual.” For this particular
configuration, a constant value is required, a slider
allows output to be precisely adjusted and then fixed at
a given value.
One unique feature of the system is that daily values
can be advanced or delayed by a specific offset,
something that has proven useful in cycling different
cohorts of brood stock in the same system.
Finally, the system offers four distinct “Programs”
that can be defined by any of the three modes, and then
“targeted” to different elements of the system. This
effectively means that hatchery managers can have
different areas of their production cycle running on
different, user-defined photoperiods at the same time.
Wherever we look in our industry, it seems new
technology is challenging conventional wisdom, and
lighting is no exception. So, perhaps the days of
slinging a low-output fluorescent bulb over each tank,
with a simple timer to turn them on and off are now
coming to an end.
“There is still a great deal to learn about how
improved lighting can benefit aquaculture outcomes”
concludes Gyles, “but for now, it is encouraging to
see more and more hatchery managers engage with
this technology as more than just a way to reduce their
energy bills.”
Image: The
Controller allows
users to select
from a number
of setting profile.
The system
matches the
photoperiod
values for a
particular
location,
including
sunrise, sunset
and the
seasonal shift in
noon intensity,
relative to winter
and summer
solstice
48 | January | February 2016 - International Aquafeed