The Great LED Debate

If you have issues getting in contact with him I will personally see to it that he gets a fixture (even hand delivering it if necessary) and tests it.

 

Thank you, we have sent him an email, and are awaiting his response.

 

Good to here. Is the Supernova ready for testing?

 

gcarrol, it is almost there. That sucker will get some spread, those XT-Es are bright 8)

 

And Greg, the Orphek retailers claims were very outlandish compared to ours, I am saying that about 120watts of LED power can replace 250 watts of metal halide power. The case they presented was pretty much adding 5 LEDs to the 55 LED bridgelux fixture we sell, and claiming that is as powerful as 400watt mh, which is not at all true. It would take about 100 bridgelux LEDs to do the same, about 200 watts, as a 400watt mh system. I would like to see what Sanjay says, and will accept his results, even if they are not in our favor.

 

As I stated before, I am not so sure you know just how capable MH lighting can be. Comparing some of the off the shelf MH lighting that is offered out there does not even begin to compare to the hoticulture reflectors that we use. It's like night and day. I'm not saying you can't beat MH. I am just waiting for the fixture that will make MH obsolete. Keep in mind that the fixture that gets Sanjay to switch will mean instant success. I truly think you Supernova is the strongest contender I have ever seen based on what I have read (although I hope the led choices were made using a spectrometer rather than on a hope and a prayer). I hope for you that it is the one! Good luck and no hard feelings I hope.

 

Greg, I am not mad at you, and you very well may be right. If you are, I will admit if you're right, right here in this thread. And yes, we choose our LEDs for photosynthetic benefit based on a spectrometer, and all of the colors, like 420nm violets, 660nm red, 630nm red.oranges, etc. were added based on the spikes from mh bulbs, and T-5s, and what was proved as beneficial over reef tanks, by trying them and seeing what kinds of colors result in the corals, immediately and over time.

 

Radion or a DIY or customer made Cree system- what experience do you have with DIY units?

 

I think it is also important to point out that Dr Sanjay is an engineer. Also, as Alex mentioned, he is sponsored by those who produce MH products. That being said, here is a quote from Sanjay saying he thinks LEDs are more efficient on tanks under his 500 gallon- which i don;t think many of us currently own.


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You are hereCORAL Interview: Dr. Sanjay Joshi
CORAL Interview: Dr. Sanjay Joshi

By jml - Posted on 31 August 2011

“Boredom doesn’t exist in this hobby.”
Prof. Sanjay Joshi

By Daniel Knop
Excerpt from the September/October LED Lighting Issue of CORAL

Sanjay Joshi was born in 1959 and grew up in Bombay, India. At the age of 22 he emigrated to the US and now lives in Pennsylvania, where he is a professor of industrial engineering at Penn State University. Aside from his professional work, Sanjay has been a dedicated reef aquarist for decades, and because of his involvement in engineering, one of his special interests in the hobby is on the technical side: the lighting of coral reef tanks. For many years he has been analyzing and comparing the light spectrums of literally all the available lamp types used in this field. Lately he has been focussing on LED lighting.

CORAL: Sanjay, how many years have you been maintaining coral-reef aquaria? And how did you get into the hobby?

Prof. Sanjay Joshi: I have been keeping coral reef aquaria since around 1991. When growing up I was always fascinated by fish and aquariums, and I kept and bred several freshwater fish species in India, where aquarium-keeping has many serious enthusiasts. I used to spend all my little allowance on fish and aquariums. I had to give it all up when I came to the United States as a graduate student. For the next few years after coming to the US I did not have any aquariums, but admired them from afar. I was living in West Lafayette, Indiana while working toward my Ph.D. from Purdue University, and the Shedd Aquarium in Chicago was one of my favorite weekend trips. After getting a job at Penn State and purchasing a house, one of the first things I did was to set up a freshwater aquarium to fulfill my childhood dream of keeping discus. I did that for almost two years, until I walked into a store that had the most beautiful 30-gallon (114-L) reef aquarium I had ever seen. I had always wanted to keep saltwater fish and was already contemplating it. When I saw that reef tank I knew exactly what I wanted and plunged right in, and I’ve been doing it ever since. It has never become boring and has managed to keep my interest for 20 years. The size of my home tank has increased from 29 gallons (110 L) to 500 gallons (1900 L). The hobby has a lot to offer, with so many interesting life forms, challenges, and learning opportunities. Boredom doesn’t exist in this hobby.

CORAL: What do you consider to be your most exciting experience in the hobby? Some type of breakthrough? Or a certain tank you maintained successfully, for example, the big reef tank at the Penn State Student Union?

Prof. Sanjay Joshi: Reefkeeping is a very interesting hobby, and given the wide range of animals that one can focus on, there is always something new to learn. I have had success in keeping tanks large and small, both at home and at the university, and I really enjoy the learning experience each one provides. Of course, the most unforgettable experiences are the ones that deal with “disasters.” How could I ever forget the frustrated voice of my wife calling me in the middle of the night when I was in Europe to tell me there was water running out of the tank? Or the time when all the fish in the tank died overnight? But my most exciting and rewarding experiences have come from the friendships I have developed all over the world, and the opportunities to travel and see reefkeeping in different countries. Nothing beats traveling thousands of miles, seeing reef aquariums, taking road trips, and sitting over a few beers discussing reef aquariums in spite of language difficulties. We have had fun drinking wine and hanging out in coral farms in Germany!

CORAL: I‘ve been observing the development of LED aquarium lamps for many years, but it has taken a long time for them to become popular in the hobby. For years this was due to the high price and low performance, but it seems that a more favorable ratio between cost and performance has now been achieved so that the technology is starting to spread to the average user as well. What do you think are the chances that some types of LED lamps will become comparable in importance to metal halide lamps and fluorescents for growing corals?

Prof. Sanjay Joshi: The high cost in relation to performance has limited the broad acceptance of LEDs in the hobby. But, as with any new technology, it takes a while for costs to drop, and they are now not too far from those of conventional metal halide and fluorescent lighting, especially when you start to consider other factors, such as energy usage. We are seeing a lot of new medium-sized setups with LEDs. In fact, I have changed the lighting in my three smaller aquariums (less than 50 gallons/200 L) to LEDs. I am waiting for the day when it becomes cost-effective for my 500-gallon (2,000-L) tank. I can see this happening in the near future.

 

O. I have never really been interested in them. I'm a plug an play guy when it comes to lighting. I got a friend around the corner with a DIY and the wiring near the power supplies looked like a bee hive. Just not my cup of tea. That being said I would go with the Radion between the two. The one mainstream fixture that peaks my interest is the Maxspect Razor. I have a couple club members with the Maxspect Mazarra that have had really good results.