Metal Halide vs. LED Rates of Photosynthesis

[Nonya]

News

“LEDs are a rare silver bullet technology – they’re ready now, they cost half as much to run as fluorescents, and they constitute a double win for climate change mitigation and reducing toxics pollution. We were amazed to see the international cooperation on lighting at COP4. We hope for continued global alignment and momentum at COP5,” said Corinne Schneider, Chief Communications Officer at CLASP."

 

[Saltydog69]

“LEDs are a rare silver bullet technology – they’re ready now, they cost half as much to run as fluorescents, and they constitute a double win for climate change mitigation and reducing toxics pollution. We were amazed to see the international cooperation on lighting at COP4. We hope for continued global alignment and momentum at COP5,” said Corinne Schneider, Chief Communications Officer at CLASP."

wow man. I have never seen anyone so scared of mh t5 bulbs... did you get cut by one or get mercury poisoning as a kid haha... led are not even close yet to being better than mh, so you keep your leds and let us do what we do with our bulbs...

 

[Nonya]

wow man. I have never seen anyone so scared of mh t5 bulbs... did you get cut by one or get mercury poisoning as a kid haha... led are not even close yet to being better than mh, so you keep your leds and let us do what we do with our bulbs...

Scared? No. Pragmatist? Yep.
Nobody's telling you what to do with your "old standard" bulbs, except that I hope you make sure they don't end up in the landfill.
LEDs have been capable of growing great SPS ever since I built my own system a decade ago. Certain commercial fixtures are still playing catch-up to what I was used to with my DIY LEDs, but with so many people successfully growing great reefs for quite a while (as in Tank of the Month, Reef of the Month, etc.), it looks like the battle is over. Halides are no longer necessary.

 

[JCOLE]

News

If that is the same timeframe as to when the POTS telephone lines are being phased out then I think we will be fine for at least another 20 years. In my industry, I heard POTs lines were being phased out by 2013. That was in 2010 and yet, here we are. POTS lines are still here. Why? Because it is easier said than done. There is a major issue with stopping all POTS lines. Just like it would be a big issue phasing out all MH and mercury based lighting. A lot of your produce and plants are grown under MH. You cannot just cut off that supply and cost someone a lot of expenses by changing out their lighting systems without a strong replacement in place. That will take YEARS to implement and not just 2-3 years of a special council talking.

Now, whether our hobby being a Niche lighting market can sustain itself by creating hobby grade bulbs then that is the question I cannot answer. Probably not and that is the reason I am stocking up on bulbs for now.

 

[Nonya]

Now, whether our hobby being a Niche lighting market can sustain itself by creating hobby grade bulbs then that is the question I cannot answer. Probably not and that is the reason I am stocking up on bulbs for now.

I'm sure politicians are experiencing a lot of pocket lining over this one, and there must be a lot of pressure to slow-roll the ban.

I had to Google POTS. I'm sure it took a lot of time to transition the million miles of lines and supporting equipment.

As far as stocking up, I'm sure that's the smart move for MH and T-5 users. You may want to add ballasts to the list.

 

[Superlightman]

Scared? No. Pragmatist? Yep.
Nobody's telling you what to do with your "old standard" bulbs, except that I hope you make sure they don't end up in the landfill.
LEDs have been capable of growing great SPS ever since I built my own system a decade ago. Certain commercial fixtures are still playing catch-up to what I was used to with my DIY LEDs, but with so many people successfully growing great reefs for quite a while (as in Tank of the Month, Reef of the Month, etc.), it looks like the battle is over. Halides are no longer necessary.

I think you still not get the point.Yes leds can growth corals but less good than halides and t5 , I went full led but then had to switched back because they never gave me the same results and I had what is considered the best on the market.If they had work, believe me, I still would use them alone. You not understand that if so many people switch back or ad t5 to the led it as nothing to do with loving led or not but with the results that not give you same growth and coloration. The day they will really work I will stop use the t5 but until now I not found such a led even if the marketing claims it.

 

[Nonya]

I think you still not get the point.Yes leds can growth corals but less good than halides and t5 , I went full led but then had to switched back because they never gave me the same results and I had what is considered the best on the market.If they had work, believe me, I still would use them alone. You not understand that if so many people switch back or ad t5 to the led it as nothing to do with loving led or not but with the results that not give you same growth and coloration. The day they will really work I will stop use the t5 but until now I not found such a led even if the marketing claims it.

I do get the point; however, my experience was that my corals responded almost immediately to LEDs. Better growth, better color than 400W 14,000K MH and VHO actinics. Which LEDs were you using?

 

[Superlightman]

I do get the point; however, my experience was that my corals responded almost immediately to LEDs. Better growth, better color than 400W 14,000K MH and VHO actinics.

Well not for most of us, or maybe you had not good lights prior, or you have to sell you own leds because the available not give us satisfaction ;-)

 

[Nonya]

Well not for most of us, or maybe you had not good lights prior, or you have to sell you own leds because the available not give us satisfaction ;-)

My best LEDs were DIY. I'm using Radion Gen 3 Pros at the moment, but I will be building DIY LEDs for my two large tanks this year. What were you using?

 

[Superlightman]

My best LEDs were DIY. I'm using Radion Gen 3 Pros at the moment, but I will be building DIY LEDs for my two large tanks this year. What were you using?

Radions g5 + orphek bars on my last set up

 

[Shooter6]

I thought this thread got shut down and closed for comment a couple weeks ago?

 

[Nonya]

Must've been of the sister threads. I think there are many like it.
Feel free to join in the friendly discussion.

 

[Shooter6]

Must've been of the sister threads. I think there are many like it.
Feel free to join in the friendly discussion.

I thought it was the one you requested be closed in a post.

 

[MnFish1]

wow man. I have never seen anyone so scared of mh t5 bulbs... did you get cut by one or get mercury poisoning as a kid haha... led are not even close yet to being better than mh, so you keep your leds and let us do what we do with our bulbs...

I'm curious - did you read the title of the post and the associated data? I'm not asking to be snarky - I'm curious about your opinion as to the results presented on page 1.

 

[minus9]

I'm curious - did you read the title of the post and the associated data? I'm not asking to be snarky - I'm curious about your opinion as to the results presented on page 1.

I did and I really wasn't surprised by the data at all. It's like comparing a garden hose (LED) to a fire hose (MH). If one light source is only producing a limited number of wavelengths to another source that's producing a "full" spectrum of wavelengths, it's no wonder it takes longer for the LED to hit photo-inhibition. If your take away is LED's are better, then you've completely missed the data, plus I don't think it was @Dana Riddle point, other than the fact that it was interesting. This is not a jab at you, merely an observation with this whole thread. I didn't come away with the thought that one was better than the other, just a simple observation.
Happy reefing!

 

[MnFish1]

I did and I really wasn't surprised by the data at all. It's like comparing a garden hose (LED) to a fire hose (MH). If one light source is only producing a limited number of wavelengths to another source that's producing a "full" spectrum of wavelengths, it's no wonder it takes longer for the LED to hit photo-inhibition. If your take away is LED's are better, then you've completely missed the data, plus I don't think it was @Dana Riddle point, other than the fact that it was interesting. This is not a jab at you, merely an observation with this whole thread. I didn't come away with the thought that one was better than the other, just a simple observation.
Happy reefing!

I came away with the idea that in the type of coral studied - with the lights used - that "At lower light intensity (up to about 200 PPFD), there is very little difference. Greater than 400, the differences are huge." (Quote from Dana).

I was not trying to suggest that this experiment shows MH are 'worse" or LED are "Better". I'm not sure you can say that the wavelengths produced are comparable between a garden hose and a firehose - though many people say this. And I (think) I agree with you that some of the conclusions of this experiment do not reflect the 'purpose' of the experiment.

 

[oreo54]

If your take away is LED's are better, then you've completely missed the data, plus I don't think it was @Dana Riddle point, other than the fact that it was interesting. This is not a jab at you, merely an observation with this whole thread. I didn't come away with the thought that one was better than the other, just a simple observation.

"sigh"..
The higher the rETR the more photosynthesis..
So you are looking at it completely wrong.
It has little to do with when inhibition occurs but more how much more photosynthesis occurs before inhibition.
Or how much more photosynthesis at a set par value.

That "firehose" is less efficient and shuts down the corals sooner.

and YES , just a one of ect ect. so it shouldn't be taken too seriously.

Aquation Scientific Equipment » A Guide to Analysing Rapid Light Curves

aquation.com.au

Example @ 400 photosynthesis efficiency is 115/400 and 90/400
Which one is greater? .28 vs .22

 

[minus9]

I came away with the idea that in the type of coral studied - with the lights used - that "At lower light intensity (up to about 200 PPFD), there is very little difference. Greater than 400, the differences are huge." (Quote from Dana).

I was not trying to suggest that this experiment shows MH are 'worse" or LED are "Better". I'm not sure you can say that the wavelengths produced are comparable between a garden hose and a firehose - though many people say this. And I (think) I agree with you that some of the conclusions of this experiment do not reflect the 'purpose' of the experiment.

True, that's the other factor, species of coral. Not all are equal in their ability to adapt to lighting changes/intensities. My point about the hose analogy is based on the fact that this experiment wasn't comparing two identical spectrums of light, but two vastly different spectrums or lack of. This is apples to oranges at best.

 

[MnFish1]

The higher the rETR the more photosynthesis..

Another interesting 'point' or question is 'does increased photosynthesis actually mean its a positive for the coral. For example - One comment I've read is that increased photosynthesis can cause increased free radical formation - which can also damage tissue. Higher flow can mitigate this - again from my understanding - to an extent.

 

[minus9]

"sigh"..
The higher the rETR the more photosynthesis..
So you are looking at it completely wrong.
It has little to do with when inhibition occurs but more how much more photosynthesis occurs before inhibition.
Or how much more photosynthesis at a set par value.

That "firehose" is less efficient and shuts down the corals sooner.

and YES , just a one of ect ect. so it shouldn't be taken too seriously.

Aquation Scientific Equipment » A Guide to Analysing Rapid Light Curves

aquation.com.au

Example @ 400 photosynthesis efficiency is 115/400 and 90/400
Which one is greater? .28 vs .22

I got it, MH is the firehose. My point is that the spectrums are not the same, not even close. It makes total sense that halides will shut down sooner because of the broader spectrum of light the coral has to absorb.