PDA

View Full Version : Thinking out loud about reef lighting



hooked
01-02-2013, 08:27 PM
Iím thinking out loud here about the lighting on my tanks. I am going to verbalize what is rattling around in my head. Feel free to read this and contribute your opinion.
Since I started my reef tanks, I would take monthly pictures of them all. I started doing this to document changes in the tanks.
My 90 gallon tanks was lighted with a dual metal halide fixture with 250 phoenix 14k DE bulbs and 2 100w VHO actinics. I started this tank in Sept of 2007. In March of 2011 I made the switch to LEDís. I researched spectrums and Lumens, then designed a fixture to my liking. At first I had way too much light on things. My corals reacted in a very negative way. I turned to volume down on the LEDís and in time my corals rebounded.
Today, I spent several hours going through all of my pictures of the progress of this reef tank. Now Iím going to share my thoughts on the difference between LED and HQI. Since I switched to LEDís, I have had zoa colonies that would grow but not to any great rate. I have also noticed that my corals in general are not as robust with LEDís as they were with HQI. Just not as beefy any more. I can look at my corals that I had back then and tell when I made the switch.
My 180 gallon tank was lighted with T5 bulbs. It was started in may of 2010. This tank showed growth like no other tank that I was involved with. It surpassed my 90 with LEDís in only a years time. A side by side comparison.
My frag tank still has a 250w metal halide over it and it has crazy growth.

Now to explain my theory as to the popularity of the LED phenom. Once the blue LEDís were turned on. People saw the colors and were in love with what they saw. The size of the polyp didnít seem to matter any longer because of the color pop.

I am thinking about hanging my metal halide fixture back over my 90 gallon to see if any of this is true. I liked my corals better back then. They just look better now. I can still run blue LEDís over them at night.
As for my 180. When I get it up and running again. It will continue to have T5 lighting with LED actinics.

Let's have a discussion about this. Your input is important.

Campbell
01-02-2013, 09:15 PM
I would definitely agree with the "color popping" craze. Most people I've talked to that have run halides and switched to LEDs will still say that they loved their halides. I was torn between the halides and LEDs as well when I first got my 90g... With the halides that were originally on it, I got explosive growth but the colors didn't pop nearly as much and I definitely wanted my tank to pop like I had seen so many others' and so I jumped on the LED bandwagon also... I do believe that when I get my frag system going I may have to run halides for just pure growth rate...

I do however get an ok growth rate in my display with the 120w 2:1. I haven't tried t5 yet besides supplemental actinics with the halides but from what I hear, I wouldn't be opposed to trying that over the frag system either...

I'm considering adding a t5 setup to supplement my display actually.. I've seen this done with LEDs and shows great growth...

If you ran halides with blue LEDs to keep that color, would that be just too much lighting? That seems like it would be extremely heavy...

Murfman
01-02-2013, 09:45 PM
Lots have had this discussion, over on Reef2Reef and RC. Seems like the way a lot of hobbiests are going is MH with T5 and LED supplement.

Coral Xpressions
01-02-2013, 10:15 PM
I've run nothing but LEDs on my tanks so have nothign to compare to personnaly but I've heard nothing but great growth with T5. I've been giving alot of thought to hooking the T5 setup that originally came with the tank back up to supplement my LEDs to try and get more growth. As soon as I can figure out how to get it working and blot it in I would be more than happy document growth compared tp whatI have seen thus far.

Dstyrc
01-03-2013, 12:45 PM
So i've never ran LED or Halide's but i want to just jot this down. I've always ran with T5's and have been majorly jelous of LED and MH users. However i always felt my growth was really good so i've decided to stay with t5's. After reading many forums and now this thread i think my mind is made up and i will have to rate lighting in this order. MH > T5 > LED

hooked
01-03-2013, 01:04 PM
I don't thing that growth is an issue. My corals are growing fine. The difference that I am seeing is my zoa coloties are fuller with metal halide. My SPS stalks are thicker with MH. The T5 lighting has paralleled the MH. Just a color difference in the corals.
My new direction is to find out what the LED's are missing, and add it to my system.

SpaceOps
01-03-2013, 01:14 PM
IMO, LEDs are the way to go. There are just too many advantages:
- Initial cost is reasonable and getting better.
- Some LED setups allow you to adjust the spectrum to your personal taste
- The cost to operate is as low as 20% of MH (I replaced over 1200W of MH and VHO with 240W of DIY LEDs)
- By selecting the proper wavelengths, you can provide exactly what your corals will need. Once acclimated, my coral growth went bonkers with the LEDs. I actually bleached them at first because the blues were overloading the photosynthetic apparatus.
- LEDs operated within their design limits can last 10 years with only 3% degradation per year. MH and VHO need to be replaced every 9 months or so.
- LEDs won't heat your water.
- With the right driver/controller, any LED is dimmable.

I believe the reason so many people still aren't sold on LEDs is because they think visual brightness and high PAR are what all corals need. With a 6500K MH of sufficient wattage, you can get a PAR reading of 400 at two feet depth and your corals will do reasonable well; however, with the right wavelengths of LEDs (400-500 nanometers (NM) producing only 100 PAR at two feet, you can get much better growth and pigmentation than with the MH. That's because not all PAR is the same. Photosynthesis in corals is much more efficient in the blue-violet part of the spectrum, and some spectral regions (yellow, orange, red) have little effect on coral photosynthesis, even if their PAR readings are extremely high.

I'm beginning my next tank build. When it comes to lighting I'll be using the lighting data I collected and presented here to design and build my LED system (Hopeful that Doyle will evaluate the LED driver chips before I choose my driver setup...hint): http://www.thescmas.com/forums/showthread.php?11300-Here-s-the-research-supporting-my-next-DIY-LED-project

SpaceOps
01-03-2013, 01:18 PM
I don't thing that growth is an issue. My corals are growing fine. The difference that I am seeing is my zoa coloties are fuller with metal halide. My SPS stalks are thicker with MH. The T5 lighting has paralleled the MH. Just a color difference in the corals.
My new direction is to find out what the LED's are missing, and add it to my system.

Doyle, don't you have the ability to measure the spectral parameters of your MH and compare it to what you have now?

freedominco
01-03-2013, 01:20 PM
I have LEDs on my 180, only 2 120 watt units so my tank is a little under lit, my growth on something's are really good others just ok, the color in my opinion is way better then any t-5's I use to run. I was over at Marty's the other night for the first time in a few months and his growth was amazing way better then any growth he seemed to have when he was running his halides. I think it's a combination of factors the lead to really good growth not just lighting. I love my LEDs and I use to be all about T-5's trying different bulb combos trying to find the perfect combination to make the tank look just right, what sucked was every 8 months it was either replace the bulbs or start to battle algae that would be caused by worn out bulbs. Anyone doubting that LEDs, even cheap Chinese LEDs when combined with the other requirements of a healthy tank can achieve rapid growth should go look at Marty's tank to see not only the amazing growth but also the size and healthiness of his corals.


Sent from my iPhone using Tapatalk

SpaceOps
01-03-2013, 01:31 PM
My point was that when all other factors are the same, the right choice of LEDs can actually provide as good as or better coral growth/health than MH or T-5. I think the MH and fluorescent technologies are on their last legs. MH cost too much to run and replace over time and have heat issues, and while energy efficient, fluorescents will always have the issue of rapid spectral degradation. Properly designed (that is, not over-driven) LEDs may outlast your tank.

Whether you use MH or standard size LED systems, it's normal to have three over a 6 foot tank because of the "beam" width.

hooked
01-03-2013, 01:36 PM
I'm working with engineering at onsemi right now. These driver chips all smoked when set to over 424mA. They don't think that is possible. I am using their eval board so it's not my circuit. I'll keep you posted on what they come back with. They are planning to send an engineering rep down from denver to work with me on these. At this point I am not impressed. I like robust designs. These ar eappearing to be very sensitive.

freedominco
01-03-2013, 01:53 PM
My point was that when all other factors are the same, the right choice of LEDs can actually provide as good as or better coral growth/health than MH or T-5.

I completely agree



Sent from my iPhone using Tapatalk

SpaceOps
01-03-2013, 01:58 PM
my growth on something's are really good others just ok

I think that would be the case with any type of lighting. Unless your corals all originate from a single depth, meaning the same lighting conditions, some will do better than others. Shallow water corals do better with lighting conditions similar to shallow water conditions, while deeper water corals do better with deep water lighting conditions.

It's in this paper: http://jeb.biologists.org/content/212/5/662.full.pdf "There was a clear and significant relationship between colony depth and photosynthetic performance under blue light spectra. Deep corals showed higher photosynthetic performance when they were exposed to blue light in comparison to full PAR illumination under the same light intensities...Shallow-water corals showed the opposite response, with higher photosynthetic performances under full-spectrum PAR than under the blue light."

freedominco
01-03-2013, 01:59 PM
Whether you use MH or standard size LED systems, it's normal to have three over a 6 foot tank because of the "beam" width.

I have a center brace so 3 fixtures won't work since I already have 2 120 watt fixtures I would like to add 2 more. I know 2 other 6 foot tanks and they both run four, if I could do it all over I would like 2 200 watt fixtures.




Sent from my iPhone using Tapatalk

SpaceOps
01-03-2013, 02:00 PM
I'm working with engineering at onsemi right now. These driver chips all smoked when set to over 424mA. They don't think that is possible. I am using their eval board so it's not my circuit. I'll keep you posted on what they come back with. They are planning to send an engineering rep down from denver to work with me on these. At this point I am not impressed. I like robust designs. These ar eappearing to be very sensitive.

I thought you were using the chips alone. Shoot, I was hoping they'd work out. They can be used with the Arduino PWM output.

freedominco
01-03-2013, 02:03 PM
I think that would be the case with any type of lighting. Unless your corals all originate from a single depth, meaning the same lighting conditions, some will do better than others. Shallow water corals do better with lighting conditions similar to shallow water conditions, while deeper water corals do better with deep water lighting conditions. It's in this paper: jeb.biologists.org/content/212/5/662.full.pdf

The same thing would happen when I used the t-5's some things grew better then others. It's a constant game trying to find the best spot for all the different corals and their requirements.


Sent from my iPhone using Tapatalk

SpaceOps
01-03-2013, 05:03 PM
I have a center brace so 3 fixtures won't work since I already have 2 120 watt fixtures I would like to add 2 more. I know 2 other 6 foot tanks and they both run four, if I could do it all over I would like 2 200 watt fixtures.

3 could still work. The blue wavelengths usually pass through glass or acrylic pretty well. You could always DIY something for the middle of the tank and have the two others at either end.

Romebaby
01-03-2013, 05:18 PM
I was just reading an article yesterday about the wavelength corals grows best on, and I don't know how credible it was but it had the biggest spikes at 440 & 470, and 680nm. Is anyone running a significant amount of these leds on their fixtures? Most of the ones I see for sale are 455-460 and nothing in the 600 range.

Coral Xpressions
01-03-2013, 05:23 PM
I have a center brace so 3 fixtures won't work since I already have 2 120 watt fixtures I would like to add 2 more. I know 2 other 6 foot tanks and they both run four, if I could do it all over I would like 2 200 watt fixtures.


Sent from my iPhone using Tapatalk


I have a center brave also and it works just fine. My sps and clams are under it and they are loving life. Same LEDs as you have

hooked
01-03-2013, 05:56 PM
I was just reading an article yesterday about the wavelength corals grows best on, and I don't know how credible it was but it had the biggest spikes at 440 & 470, and 680nm. Is anyone running a significant amount of these leds on their fixtures? Most of the ones I see for sale are 455-460 and nothing in the 600 range.

I'm running 445nm, 465nm then my whites. 680nm is right at the wavelength that promotes plant growth. I'm afraid to put too much in tha range. However I have recently ordered LED's of thesw wavelengths. royal blue to blue - 440nm, 445nm, 450nm, 450-465nm, cyan to green - 490nm, 500nm, 520nm, 530nm, red - 620-630nm and 660nm. I don't know what quantities of each I'm going to use but I will be testing with all of them. I am also going to be testing with whites from 3300k through 20000K.

As far as the blues penetrating through the glass and acrylic. I'm not so sure about that. UV passes through water and is restricted by glass and IR passes through glass and is blocked by water. We all know that blue is close to UV and red is close to IR on the spectrum.

SpaceOps
01-03-2013, 06:28 PM
I was just reading an article yesterday about the wavelength corals grows best on, and I don't know how credible it was but it had the biggest spikes at 440 & 470, and 680nm. Is anyone running a significant amount of these leds on their fixtures? Most of the ones I see for sale are 455-460 and nothing in the 600 range.

Which article?

I think you're confusing two things, light absorption peaks and the rate of photosynthesis (photosynthetic response).

Photosynthesis (in corals) as a function of absorbed wavelength is at a max between 410nm and 465nm or so. Regardless, you don't have to provide every wavelength in that range to get great growth. Believe it or not, you can get growth with just 450nm LEDs, but the visual effect is pretty flat. I ran a combination of 450nm and 465nm blues with some whites (for visual appeal) and had great growth with just the blues, and good visual appeal when the whites were also on. The only valid reason for a reef hobbyist to consider additional wavelengths is fluorescence. You'll cause 2/3 of all known fluorescent pigments to fluoresce if you provide the majority of wavelengths between 400nm and 510nm. So far, only DIYers have done that.

Light absorption by the primary photosynthetic molecule (Peridinin-chlorophyll a-protein) does have the three absorption peaks you mentioned, but don't confuse absorption peaks with a corresponding peak in the photosynthetic response.

As far as the 600nm-700nm range, corals receive very little red light, even in fairly shallow water. There are a couple of reasons you want to avoid red light--depending on the quantity, the effects can include slower growth, bleaching, and algae blooms.

SpaceOps
01-03-2013, 06:34 PM
Doyle beat me to it.

Maybe I should have just said acrylic regarding the blues. I had the same thought re UV and glass. I'll do some reading and get the facts.

Doyle, do you plan to have the reds off except when you're looking at the corals? They do nothing for fluorescence, but some people like the extra red "pop" when they're looking at the tank.

hooked
01-03-2013, 07:01 PM
I'm going to put a couple on my display, just for visual testing. The balance are going to be over my test tanks. To positively verify if they do anything. I just need to rebuild my fixtures for isolation.


Sent from my iPhone using Tapatalk

SpaceOps
01-03-2013, 07:10 PM
The effects of red light on corals is pretty well documented. If you want, I can send you links to several sources that confirm the negative effects in regards to slowed growth and bleaching.

Coral Xpressions
01-03-2013, 09:36 PM
The effects of red light on corals is pretty well documented. If you want, I can send you links to several sources that confirm the negative effects in regards to slowed growth and bleaching.

If you wouldn't mind posting them here so we can all have a lil' informative reading :D

SpaceOps
01-05-2013, 08:01 PM
Good idea. I also mentioned them in my presentation.

• Coral growth rate is better when the amount of blue light is increased, but coral growth rate decreases when the levels of red light are increased, even when accompanied by an increase in Kelvin rating: www.advancedaquarist.com/2008/12/aafeature1 (http://www.advancedaquarist.com/2008/12/aafeature1)
Pay particular attention to the paragraph titled, "The Red Light Theory Revisited."

• Red light can cause coral bleaching: www.advancedaquarist.com/2003/11/aafeature (http://www.advancedaquarist.com/2003/11/aafeature)

• Corals have blue light-sensing photoreceptors that cue coral branching toward the blue light source, which is the dominant light in the coral environment. There is no corresponding red photoreceptor in corals: http://jeb.biologists.org/content/212/5/662.full.pdf

Romebaby
01-08-2013, 04:51 PM
SpaceOps, can you tell me what your spread is on your fixtures, something like:
400 x4
420 x8
440 x8
450 x10
460 x10
6.5k x15

And do you see any reason to mix up the whites at all or go with all 6.5K or 10K?

I'm curious in what's working for you if you're running the majority on 1 or 2 wavelengths and a couple here & there or a pretty even spread.

SpaceOps
01-09-2013, 02:19 PM
And do you see any reason to mix up the whites at all or go with all 6.5K or 10K?

On my last tank I had only cool white, blue and royal blue LEDs. It's best to evenly distribute each color to ensure equal color distribution. I like the information posted here: http://reefledlights.com/ledmytank/

There's no real need to get LEDs only 10nm apart in wavelength, but it couldn't hurt. Blue LEDs don't emit a single wavelength--they emit a range or band of wavelengths.

For my next system (coming soon!) I plan to get LEDs with center wavelengths from 420-500nm (maybe down to 400nm and up to 515nm to increase the number of fluorescent pigments that are excited).

I prefer optics to make sure the light is directed straight onto the corals and reduce the amount of indirect light reflected off the glass. Not everyone prefers optics though. You can put them on first and take them off if you don't like the effect. They're very cheap.

coach
01-13-2013, 12:40 AM
So I thought I would ask in this thread. I'm currently running 2 120 w 20 k evo led units. I, as others have stated, love my LEDs. However, I'm bored. I decided to build a canopy and add some t5 lighting to my LEDs. I ordered an ati purple plus bulb and plan on running the one t5 bulb with my leds. Please give me your opinions. Should I run more than just one of the purple plus bulbs, run a purple plus and true actinic, would this be too much blue? What do you all think.

Bigfoot610
01-13-2013, 12:59 AM
Everything needs to have the kinks worked out I have yet to see a led setup that can grow faster then a metal halide. I know it is only a matter of time untill they get there but untill then it's MH and led suplementation for me. There are alot of people switching back RC has a thread on it in the diy section. IMO its like a new version of windows never get it when it first comes out wait a few years...

SpaceOps
01-16-2013, 08:57 AM
I had better growth under LEDs than under 2 x 400W 14000K MH and 2 actinic VHOs. My next build will definitely be 100% DIY LED-based, to include an Arduino controller if Doyle and the On Semiconductor engineers can determine if the constant-current CAT4101 chip is suitable for use.

I'm fairly certain that people are switching back because they got LEDs that are either not putting out enough for their corals' needs, or because they prefer the visual intensity of MH. Current ready-made LEDs tend to be very blue, which is exactly what corals need, but they aren't visually bright enough in some people's opinion. Old ways die hard (How long ago did everyone think 6500K was the best light for coral growth?). It'll take a while for people to learn that visual brightness doesn't always mean better growth.

My solution would be to have extra whites to use when you're viewing.

Noob
02-15-2014, 10:25 PM
I have used T5's, MH's, and LED's. I too saw better growth under the MH's but I also struggled with temps and had to use T5's and LED's over the brace so I didn't burn a hole in my tank. I also had this crazy fear of burning my house down. ha ha

I still use LED's (my third fixture), and I am not sure I will every go back to MH, but I do believe it depends on the quality of your LED's and your water quality. Perhaps I was more critical with my water quality when I had my MH's?