Anyone Thinking of Dumping LEDS and going back to Halides

[oreo57]

Yes you can...but the "nearly" doesnt go far enough in my humble opinion. Im thinking we need a spread from 365 up to 430, so like using a 365 base with a phosphor emitted range covering all frequencies up to 430, not just discrete ones at specified frequencies.

That is what they "found" w/ hort. LEDs.. No need to do rb /deep red when one can take a rb and add broad spectrum deep red phosphors, covering a wide swath of the red spectrum from near IR to orange..
no data on effectiveness that I know of.
FUNNY thing is they are sold as "full spectrum" LED's..

One thing though, on a general level phosphor decay over time is still an issue, not so much w/ discreet color LEDs..
How much of an issue????

There seem to be tons of solutions to tons of "problems" (defined and undefined) that just don't get done for one reason or another.. "sigh" human nature..

 

[karimwassef]

horticulture avoids UV. It's counterproductive for them.

UV is important for coral coloration and pigmentation. Different UVs have different impact.

I'm not arguing against the lack of their inclusion in white LEDs. Just that UV LEDs are common and easily used in any design.

 

[Aqualund]

horticulture avoids UV. It's counterproductive for them.

UV is important for coral coloration and pigmentation. Different UVs have different impact.

I'm not arguing against the lack of their inclusion in white LEDs. Just that UV LEDs are common and easily used in any design.

Just to be clear, are you completely discounting the role of Chlorophyll A in SPS photosynthesis? If so, what is the basis of your opinion...do you have a study or a paper that explains this?

I also question your horticulture reference in that they avoid it because it's counterproductive. Maybe someone should tell GE?

http://www.gereports.com/post/91250246340/lettuce-see-the-future-led-lighting-helps-farming/

 

[gus6464]

horticulture avoids UV. It's counterproductive for them.

UV is important for coral coloration and pigmentation. Different UVs have different impact.

I'm not arguing against the lack of their inclusion in white LEDs. Just that UV LEDs are common and easily used in any design.

Horticulture avoids violet because red diodes are much cheaper and they don't have to worry about visual aesthetics. That's it. Watt for watt violet LEDs produce more chlorophyll A PUR than red but red is a lot cheaper.

 

[Aqualund]

Horticulture avoids violet because red diodes are much cheaper and they don't have to worry about visual aesthetics. That's it. Watt for watt violet LEDs produce more chlorophyll A PUR than red but red is a lot cheaper.

There are also effects with different spectrum of light with regards to whether the flower will flower or not, or whether they want it to.

So yet another notch in the ole "spectrum matters" belt.

Source: Pot growers

 

[karimwassef]

Just to be clear, are you completely discounting the role of Chlorophyll A in SPS photosynthesis? If so, what is the basis of your opinion...do you have a study or a paper that explains this?

I also question your horticulture reference in that they avoid it because it's counterproductive. Maybe someone should tell GE?

http://www.gereports.com/post/91250246340/lettuce-see-the-future-led-lighting-helps-farming/

where did I discount anything in SPS photosynthesis?

I said horticulture avoid UV, not LED.

 

[karimwassef]

my personal experience with UV for plants is my current design for a greenhouse. I've been asking multiple suppliers to provide non-UV blocking panels.

Unanimously, ALL rejected my request saying that no one in horticulture intentionally includes UV due its detrimental impact on plant growth.

They could all be lying, but since I'm willing to pay extra - I don't see why they would.

I finally found ONE source that disagreed with this and I followed it to a special laminate that allows UV in

http://glasslaminatingsolutions.kur...l-garden-uses-special-uv-transmissible-glass/

Here's my thread on the topic.

http://www.reefcentral.com/forums/showthread.php?t=2537919

and here is the high UV transmission laminate material called "SentryGlas N-UV" from Dupont

http://glasslaminatingsolutions.kura...att_SG_NUV.pdf

http://glasslaminatingsolutions.kura...tryglasr-n-uv/

http://www.newglasstech.com/download...20brochure.pdf

http://www.vitrum.ca/cms/wp-content/...yglas_plus.pdf

http://www.viracon.com/pdf/ProductGuide.pdf

 

[Aqualund]

where did I discount anything in SPS photosynthesis?

I said horticulture avoid UV, not LED.

Sorry, I thought by your statement that you were inferring that UV is only used for coral pigmentation and coloration.

 

[oreo57]

my personal experience with UV for plants is my current design for a greenhouse. I've been asking multiple suppliers to provide non-UV blocking panels.

Unanimously, ALL rejected my request saying that no one in horticulture intentionally includes UV due its detrimental impact on plant growth.

I finally found ONE source that disagreed with this and I followed it to a special laminate that allows UV in

Personally, you are making this a bit too simplistic. The 100% UV state was for making the environment as "natural" as possible..
That does not exactly translate to "optimum" growing conditions..
Best I can see on a very short peek is 1)UV may inhibit some pathogens 2)UV may stimulate some flowering 3)May even increase some "important" chemical production.
BUT overall health from a production standpoint is questionable, not to mention the health of equip. and workers...

Though not all the plant responses demonstrated as the result of UV radiation are considered as damaging or disadvantageous for the plant; the majority of evidence indicates that UV irradiation is usually detrimental, particularly UV-B irradiation (Caldwell, 1971). In this section a summary of the UV-B effects on crops from the literature will be presented. The growth of many plant species is reduced by enhanced levels of UV-B radiation (Teramura et al., 1989).

http://uvb.nrel.colostate.edu/UVB/uvb_agagrresearch.jsf

Uv is like anything, more than one sided..

With enhanced UV-B radiation photosynthesis decreases, plant height and leaf area decrease, dry matter production, yield and quality reduces in many crops. In the study conducted by Tevini et al. (1991b) plant height, leaf area, and the dry weight of sunflower, corn, and rye seedlings were significantly reduced with enhanced UV-B radiation. Rice is among the most important crop plants in the world. Sixteen rice cultivars from several different geographical regions were grown in greenhouses with supplemental levels of UV-B radiation (Teramura et al., 1991). Alterations in biomass, morphology, and maximum photosynthesis were determined. Approximately one-third of all cultivars tested showed a statistically significant decrease in total biomass with increased UV-B radiation.

since "sunburning" anything seems to increase pigment production for survival, well.................
BUT as most things conflicting info abounds..:

In conclusion, the UV-absorbing films tested can effectively reduce aphid abundance and spread of winged forms inside the greenhouse and protect lettuce plants from aphid infestation. Also, these films proved to be very useful in reducing the spread of aphid and thrip-transmitted virus diseases infecting lettuce.

https://www.google.com/url?sa=t&rct...pr4YuReeQ&sig2=ZxkrPjUmyNwIWIOI3SYPGA&cad=rja

In Sweden, the majority of vegetable crop plants is produced in greenhouses, in which the UV component of sunlight is lacking. This results in stragglier more vulnerable plants with lower nutritional value. Low doses of supplementary ultraviolet light can compensate for this by regulating plant morphogenesis and metabolism via dedicated UV-B photoreceptors.

https://www.oru.se/english/research/research-projects/rp/?rdb=p1298

funny huh..

http://www.ciesin.columbia.edu/docs/011-467/011-467.html

 

[power boat jim]

This thread has morphed into a highly technical dicussion of LED development and manufacture and now its uses in agriculture. Maybe its time to put some of this info under a seperate LED thread and put a sticky next to it to use for easy future reference.

There is a ton of info here that will be lost and would may be better served as a referece rather then under a discussion of going back to MH from LED thread. Just a thought.

 

[oreo57]

This thread has morphed into a highly technical discussion of LED development and manufacture and now its uses in agriculture. Maybe its time to put some of this info under a separate LED thread and put a sticky next to it to use for easy future reference.

There is a ton of info here that will be lost and would may be better served as a referece rather then under a discussion of going back to MH from LED thread. Just a thought.

Agreed (and apologize, just my nature), but it was just a temporary diversion..after 221 pages of.........

but it does have a moderate relationship i.e certain LED "lack" of certain spectral components in comparison to other light sources and why someone might want to switch in either direction....

 

[DavidinGA]

Hello all, I have a 125gal reef tank with 250W Radiums on it, a little frag tank with a 250W Ushio 20k and a 60 gal frag tank with an ecotech Radion on one side and a DIY Rapid LED set up on the other side. I can't help but notice the corals and the tank just looks better under the Halides. I have never tried the ATI power Module, and am half way thinking about replacing the LED's with the power module, but then I think maybe jsut put 2 more radiums on there instead. am I crazy for wanting to replace the LED's or have any of you noticed anything similar?

I have been running leds for 3 years now and I'm considering going back to MH's myself.

My only issue with led's is growth. It seems some sps do ok, but most grow much much slower under leds.

On the flip side the options for MH have dwindled considerably now where their aren't a lot of configuration options available (or at least not like there used to be).



(getting this thread back on track....)

 

[karimwassef]

Glad I could contribute to the diversion

 

[Jeremy257]

I have a 37 gallon cube. Been up and running four a couple years with LED.. LPS was fine.. a few months back I started getting SPS fever.. growth sucks... started researching.. I'm about to upgrade to a much bigger tank (225g).. SPS only. I want to do it right. I started researching. I'm sure it may have already been pointed out somewhere in this enormous thread.. A few days ago I stumbled across an article published in January of this year.

I think we can all agree that Sanjay Joshi knows more than most when it comes to keeping a reef tank and especially lighting one. He had experimented over the years with LEDs over his smaller tanks. 2 years ago he replaced 3 400w MH over his 500g tank with 8, yes 8 Radion Pros. Right from the start.. cost is ridiculous, energy savings is negligible.

Sanjay is an expert, he utilized arguably the best LED tech at the time (and most expensive) and he can get about 80% the growth of his MH setup with most corals.. and some species he points out.. not even close to the growth of MH.

https://www.reefs.com/blog/2016/01/05/leds-500-gallon-reef/

If that's the best that Sanjay can get out of LED with his knowledge and $6k of top tech lighting I'm sure not going to bother with it. I'm going MH on the new tank for at least the first couple of years until I have a thriving reef.

I guess people need to decide what their goals are. I want to grow SPS frags into colonies as fast as I can and I'm willing to sacrifice electricity, heat and bulb changes to get my reef grown. Maybe I'll look at LEDs again in a couple of years when I have a mature reef.

 

[AZRippster]

A few days ago I stumbled across an article published in January of this year.

I think we can all agree that Sanjay Joshi knows more than most when it comes to keeping a reef tank and especially lighting one.

https://www.reefs.com/blog/2016/01/05/leds-500-gallon-reef/

Thanks for sharing, I had not seen that article. I too have noticed his statement, "I found that corals frags tend to develop a larger base encrustation with LEDs, wonder why?". Since moving back to MH/T5, some of my coral that almost became encrusters and shouldn't, have now started branching up.

 

[oreo57]

I have a 37 gallon cube. Been up and running four a couple years with LED.. LPS was fine.. a few months back I started getting SPS fever.. growth sucks... started researching.. I'm about to upgrade to a much bigger tank (225g).. SPS only. I want to do it right. I started researching. I'm sure it may have already been pointed out somewhere in this enormous thread.. A few days ago I stumbled across an article published in January of this year.

I think we can all agree that Sanjay Joshi knows more than most when it comes to keeping a reef tank and especially lighting one. He had experimented over the years with LEDs over his smaller tanks. 2 years ago he replaced 3 400w MH over his 500g tank with 8, yes 8 Radion Pros. Right from the start.. cost is ridiculous, energy savings is negligible.

Sanjay is an expert, he utilized arguably the best LED tech at the time (and most expensive) and he can get about 80% the growth of his MH setup with most corals.. and some species he points out.. not even close to the growth of MH.

https://www.reefs.com/blog/2016/01/05/leds-500-gallon-reef/

If that's the best that Sanjay can get out of LED with his knowledge and $6k of top tech lighting I'm sure not going to bother with it. I'm going MH on the new tank for at least the first couple of years until I have a thriving reef.

I guess people need to decide what their goals are. I want to grow SPS frags into colonies as fast as I can and I'm willing to sacrifice electricity, heat and bulb changes to get my reef grown. Maybe I'll look at LEDs again in a couple of years when I have a mature reef.

first let me say I agree w/ your personal analysis..
I have questions regarding any conclusions about MH vs LED.
THIS is really not "the" unknown issue:

There are still some corals where I am not seeing growth that comes even close to MH. Most noticeably A. Millepora and the green Bali Slimer. These are corals that grew as weeds under my MH, but grow significantly slower under my LEDs. It does not seem like an issue of light quantity, but I think the light quality plays a bigger role here. There is another odd observation I can make about coral growth under LEDs. I found that corals frags tend to develop a larger base encrustation with LEDs, wonder why?

Radions are quite low in broad spectrum oranges-reds and zero deep, deep red..(sub 700nm).. What doe this mean for VERY specific species
????

Problem w/ "qualitative" statements:

but grow significantly slower under my LEDs.

Has little practical meaning .. BUT IS important.
Not "growing like weeds" does not translate to not growing nor not growing at a reasonable rate ect..
Minor point..

anyways one needs a broad brush view of what he said, then decide for yourself:

Coral color has been great, and I am satisfied with the growth on most corals. I would say that the growth rate is about 80% of what I was seeing with the MH on most corals. And that is fine with me given the other benefits I gain from using LEDs, such as not having to replace MH bulbs every year, not turning on my chiller in summer, and creating dusk effects for fish spawning. I have had 100% reliability on the units, which is impressive. I was expecting to see some hardware failure, but that has not happened yet.

They are both tools to use.. each with there "specific" plus and minuses..

Kind of the whole point..

 

[Jeremy257]

Thanks for point that out AZRippster. Now that you mention it I realize that my Red Planet frag has encrusted far more than any other growth. My California Tort it's about dead even growth between encrusting and branch / tip growth.

 

[AZRippster]

Thanks for point that out AZRippster. Now that you mention it I realize that my Red Planet frag has encrusted far more than any other growth. My California Tort it's about dead even growth between encrusting and branch / tip growth.

Wow, I've seen the same thing with my Red Planet and my Oregon Tort almost died. Both have started rebounding nicely and I'm extremely hopeful with the Tort.

 

[Jeremy257]

Oreo57 - I agree agree about the tools statement. For me I want to focus on growing the frags in my immature reef quickly. That is why I wish to focus on my water quality and set and forget my MH knowing that the light is right.

 

[AZRippster]

Here is something interesting to look at. The first photo is of Sanjay's 500G after the 2 years on Radion LED. The second is his tank when he won TOTM lit by 3 - 400W Ushio 14K Metal Halide.