Tag Archives: Walter Hatch

Sustainable Science Thesis & Abstract Update

Our friend from St. Mary’s has updated us on the progress of their experiment. Best to just quote what he said.

“We are done

The research report has been submitted as a senior thesis and is on file in our library.
I am planning to add a Marine microcosm sustainability page to my web site and I will upload the complete study to that page as well as an  annotated  the version for a general (but marine aquarium savy) audience as well as the abstract of the study abstract.

St Mary’s College is proud of their “Green campus ” awards so the page will focus on “Sustainable Science”  from the viewpoint of natural resources (the reefs) materials (the actual microcosm) and energy usage.

The soft corls (Sarcophyton) show no statisticaly significant difference with respect to the light source.  The paper explains how this may result from the difficulty in obtaining reproucible samples.

The Zooanthid (Playthoa) and hard coral (Galaxia) however did show statissticaly significant improvement in growth of the coral ans well as the zooxanthallae  count and chlorophyl content.

The web site will include facility description and brief synopsis of the research conducted.  I will include photos. Bottom line: there is statistically significant scientific evidence that the hard coral and zooanthid tested  will show improve growth and health with LED illumination. We present energy use statistics to indicate a dramatic reduction in energy use and of course increase in the sustainability of marine microcosms using solid state lighting.”

Kendal abstract

Above is the Thesis and Abstract of the experiment done by Dr. Hatch’s students. They specifically look at three different lighting types and compared growth. There was significant difference between the variables!

These studies will be linked to from this blog as soon as they are received!

LED experiement, more growth

My opinion, which is in no way the end all for the reasoning of this experiment.

Dr. Hatch came to know the LEDs he choose for this experiment, by understanding the TMC AquaRay LED line is a brand advertising,  they use less watts to get quality growing energy. Some claims, is that there will be more growth, because the spectrum in the fixture are selective, licensed, and patented. As a base line, even if these 30 watt fixtures can go the same as another 120 watt LED, or 250 watt MH… The fixture is doing it with only 30 watts.

The statement can be made, watt per watt, for LEDs available to date, these LEDs have the most useful amount of energy. As in, growth was increased compared to VHO and MH at only 30 watts of quality light spectrum.

Was this experiment testing LEDs compared to other LEDs… No.

There’s really no need for this study as there are so many variables (different spectrum and amount of spectrum) which can affect the experiment. There’s no benefit for someone running a large LED study like this.

120 watts LEDs could have been included in the experiment to add another variable, but there are so many combinations of 120 watt fixture, some included user features like dimming, so what would it really proved?

How are these fixtures different? It’s in the way they drive the energy from the fixture. Emitter didoes can be designed to be under driven or driven at a certain voltage. Many 120 fixtures use many emitters and under drive them. Some less watt fixtures drive their emitters at a higher voltage, but use less emitters.

What this study does shed light too, is that even with 30 watts of high output LEDs (of known useful growth spectrum, not color spectrum), growth will be better than VHO and MH. Certain corals at that (interesting how it’s the “higher light” requiring corals at that, not the soft corals, known for requiring less light. Growth maxed out?) As all different species of plants and corals, could grow different under different spectrum or require different amounts of light.

The spectrum being provided for this experiment, was focused on Chlorophyll Synthesis of Chlorophyll A & B. Color was a moot point as it was not the focus of the study. Even though, color was not an issue, which we can see from pictures. So, with 30 watts of high powered LEDs, great color is still present, which many people question.

More info on PAR/PUR and Chlorophyll Sysnthesis

Great job Dr. Hatch and students. Looking forward to the journal review of the experiment.


Experiment Update 2

LED versus MH, spawning, experiment

University level observation of MH vs. LED

This experiment is close to two weeks from being completed. As the results are still coming in, here is the update we do have based on observation.

From Professor Walter- St. Mary’s College of Maryland University

It is very clear that over all growth was enhanced by TMC Ocean blues.  We are processing zooxantheallae counts, total protein analysis, total chlorophyll etc through stats now.
An interesting aside: Late in the afternoon of the 19-21 (New moon) Most of the Galaxia under LED illumination spawned (several hundred colonies).  The water was nearly opaque with gametes down current from the coral. Both the eggs and sperm were viable and fertilization resulted in viable embryos although I only followed the development of a few to the 8 and 16 cell stage. 
None of the 10 colonies under VHO’s and none of the 10 under Halide in this experiment spawned.   None of the hundreds that did spawn on this occasion did so over all of the years that they were under halides or VHO’s

More will come of this experiment. This is exciting work done at St. Mary’s College of Maryland. Hopefully, this study will give some real proof to what LEDs can do. Many people switch to LEDs from MH or other and they may see a difference. But very few people are running controlled tests such as this.

The most likely reason, this spawning reaction is happening for the corals under LEDs, is due to the more USEFUL light LEDs provide. Even more so for the TMC AquaRay LEDs, as they have the most ‘useful’ light per LEDs available to the hobby to date.

PUR (useful light) VS. PAR

Experiment Update 1

Here is the latest on the LED marine coral experiment.

We will keep a photographic record of the light comparisons, but it is unlikely that they will show growth differences in only a month (maybe 2).  The corals will have changed color in that time period (even when photographed with flash)  This reversible color change occurs within a month, and we are using it as evidence that the corals have adapted to their lighting.  Additional anecdotal evidence is accumulation as well. About 25% (6 colonies) of Galaxia under LED for 4 weeks now have entered an aggressive growth phase.  This is indicated by the production of large sweeper tentacles that digest neighboring coral.  None of the Galaxia (400 colonies) under VHO or Halide are showing sweepers.  All of the corals are in the same water, at the same temperature and flow rate.  Only the light is different.

With respect to the photos, I am finding the color balance dramatically shifted toward violet.  This produces an image that does not resemble the subjective evaluations my eyes provide.  Have you obtained representative photos.  Remember that our entire 2000 gal system is a collection of raceways; The water is less than 6 in deep and there is no viewing glass.
Included are a few urchin spawning shots  and a Platythoa. Aquarium LED experiment, study, best aquarium LED
Aquarium LED experiment, study, best aquarium LED
Aquarium LED experiment, study, best aquarium LED

And, so it Begins. How to Mount?

Part of the challenge before experiments can even be ran is figuring out how to use all of the equipment to suit what needs to be done. The design of where all the corals are being watch is like a “raceway”. Not normal tank standards. These raceways a long and short. Figuring out how to mount any lighting over style of tank would be a challenge.

Here’s what the guys at St. Mary College of Maryland figured out.

AquaRay LED Mounting

TMC AquaRay DIY Mounting

AquaRay LED Mounting

TMC AquaRay DIY Mounting

The lamps are mounted on a PVC plate that is attached to J hooks.  The J hooks are suspended from a pvc frame that is held by I beams above the tank.  The lamps can be slid along the I beam or back and forth across the pvc frame or up and down by repositioning the j hooks.

There are 8 units installed over the cloning facility and display tank as well as 8 units installed over the main research tank – 8 more tomorrow.  Eight more over the holding tank next week.

The display and cloning tank have been operational for several weeks now.  Eight  LEDs are replacing 8 175W 10,000 K Halides (two year old bulbs).  The halides were delivering a Par of 39 and the LED’s 62 uM photons/M^2/sec.  Anecdotally, all to the animals look better as fluorescence was dramatically enhanced by the increase in hight frequency light.  Polyp extension appeared increased and color was more vibrant.  Only one species (Sinularia) objected to the switch and required two weeks to acclimate to the lights.

The man behind the study

Meet the man, which has brought this whole study together.

With government funding to upgrade the lighting in the biology research lab, he knew it was the right time to upgrade to one of the highest useful light LEDs on the market today. These science focused LEDs were the reason for the switch to the AquaRay LEDs.

Walter Hatch

Professor of Biology

Departments: Biology
Office: Schaefer 218
Email: wihatch@smcm.edu
Phone: 240-895-4368

AquaRay LEDs, Aquarium LED Research, Study, best aquarium LEDs, PAR, PUR


B.A. Tufts University 1961; MS Tufts University 1965; PhD Boston University marine Program 1974

Research Interests:

My research interests are in the areas of environmental physiology and chemical ecology of tropical marine invertebrates.  My students and I are currently working on the chemistry and ecological significance of toxins produced by marine flatworms.  We are also investigating the chemistry and ecological significance of molecular communication in soft corals and zooanthids. The organisms we work with produce other secondary metabolites as well including un described antibiotics and neurotransmitters.  The projects in my lab, thus, lead to natural collaboration with Dr. Koch, Dr. Byrd, and Dr. Coughlin and their students working in the areas of natural product chemistry, microbiology, and neuro pharmacology respectively. In addition we also collaborate with Dr. Tanner on the chemical ecology of plant animal interactions.