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Old 10/15/2007, 12:50 AM   #26
RiddleLabs
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Aloha Hahnmeister,

The Germans (and many other researchers for that matter) are correct in that blue light is largely responsible for photoinhibition.
Blue light can trigger dynamic photoinhibition, which is part of the zoox's protection from excessive light. Dynamic Photoinhibition is quite normal, and part of the natural diurnal photoprotective cycles.

Now. Are lamps skewed towards the blue end of the spectrum bad for corals? The answer is 'yes' and 'no' - it depends upon the quantity or intensity of blue light. At sub-saturating intensities, blue is OK, and perfectly normal. When blue intensity is ramped upwards, the natural dynamic photoinhibition comes into play.

Dana


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Old 10/15/2007, 01:07 AM   #27
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Anyone know the par readings from the blueline 10k 250 watt bulbs ran on an electronic ballast?They have the look of a 14 k bulb.These bulbs are much brighter then my 14 k evc bulbs.


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Old 10/15/2007, 12:07 PM   #28
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Hope this question isn't too far afield.

I recently hooked up a new PC bulb to my PC fixture and it seems to have blown (I saw a reddish light near the end closest to the connector for a second and then nothing. I hooked up the old bulb and it worked as before).

The retail outlet (Marine Depot) is asking me to return the bulb to them. They say if testing shows it is defective then they will send me a replacement.

I'm thinking about the shipping hassle and also wondering if they may end up deciding it is not defective. Any opinions on whether it makes sense (the bulb cost me $28, it is a 24" 65W 10k Coralife).

Can anybody help me here?
thanks!


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Old 10/15/2007, 09:06 PM   #29
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The Grim Reefer

I was also told by a solaris rep in person that the led's are in modules for easy replacement and repair.


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Old 10/17/2007, 11:40 PM   #30
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is sanjays site working for anybody else? its not working for me. looking for info on the helios compared to xm 20k 400w


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Old 10/18/2007, 12:19 AM   #31
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Wow, that Aqua Illumination unit looks interesting. http://www.advancedaquarist.com/2007/10/review

Is there something Im overlooking in that review? I mean, my only complaint COULD be that I like a fuller spectrum, but its not really even that bad. You could pair it up with a couple T5s or something to bring up the actinic or something. But 88 watts to compete with the 250watt 20,000K XM? Thats getting better. When they hit the output of a 250wattDE 14,000K pheonix or Ushio, and only cost $500, I might have to bite.

I wonder if I can put one on my light rail... that would be sweet... my 125g lit with only 88 or so watts of LED and 216 watts of T5s. Lol. Id be growing SPS with 2.5 watts per gallon! If that doesnt destroy the Watts/gallon myth, I dont know what does... oh, wait, yeah... a skylight.


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Old 10/20/2007, 06:06 PM   #32
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Are you sure it's 88w? I think they said it saves about 1/3 energy costs compared to a XM 20000k 250w so...


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Old 10/20/2007, 06:09 PM   #33
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Check there website, I may be confused.

Reduced Energy
The AI will realize over a 1/3 savings when compared to a low output metal halide (250W). In addition, consider the energy consumed by a small (400W) water chiller, and the heat produced by the chiller that must be removed using air conditioning. The compound energy savings can be substantial.


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Old 10/20/2007, 11:01 PM   #34
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Then you have some of us that have our sumps and refudiums located in the basement and are adding heaters to keep the water temp up.

So you also have to look if 1/3 savings on the light bill will also result in a 1/3 gain in the heating bill?

Dennis


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Originally posted by kinerson
Check there website, I may be confused.

Reduced Energy
The AI will realize over a 1/3 savings when compared to a low output metal halide (250W). In addition, consider the energy consumed by a small (400W) water chiller, and the heat produced by the chiller that must be removed using air conditioning. The compound energy savings can be substantial.



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Old 10/20/2007, 11:21 PM   #35
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Lets say your using a pair of Metal hides using a total of 3 W=KWH per day. If these lights reduce your usage to 2 KWh per day and your electric charge is 0.11 per KWH hour then you are saving 11 cents per day in electrricity. Now at a cost a 2,490 for a 4" system it will take you 62 years of energy savings to make this upgrade economical.

But if going to have to by a light fixture anyway then you might be paying $500 to $1000 for it so you would only be paying an added $1,500 for this fixture. so you would have pay it off much quicker.

Now there may be added saving an bulb replacement costs though. With the MY T-5 fisture you would be spending about $100 a year on bulbs. But for the LED's we do not know how long they will lst and what replacemments will cost.

Dennis




QUOTE]Originally posted by kinerson
Are you sure it's 88w? I think they said it saves about 1/3 energy costs compared to a XM 20000k 250w so... [/QUOTE]


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Old 10/21/2007, 01:54 AM   #36
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kinerson, the wattage of the unit is given right in the title of the review, and its output is said to be greater than that of the 250watt 20,000K XM. Now, that doesnt sound that impressive... Ill give you that... but its 88 watts vs. 250! Thats an electrical savings of about 65%.

Now, to get the light equal to that of a pheonix 14,000K or ushio 10/14,000K, I would need two of the 12" units... so its not a total match because the halides I normally use.

Im sure sometime in 2008, these LED units will start to look like apppealing alternatives more... able to compete with 400watt 20,000Ks with 1/4 the energy.


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Old 10/22/2007, 11:14 AM   #37
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http://www.advancedaquarist.com/2007/10/review

I have issues with the way Danna submitted the testing results for the Aqua Illumination fixture.

1) Who is going to mount their lighting fixture 1" above the water surface? The article says the legs were removed from the AI unit & 1" above the water surface.

2) The PAR charts representing AI vs the tested MH use different colors, giving the illusion the AI fixture has more PAR.

3) As mentioned before. No one who wants good growth is going to use the MH unit used in the comparison.


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Old 10/28/2007, 10:44 AM   #38
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TropTrea, and others....

Quick note on energy costs..Formula is Watts divided by 1000=KW
KW x your electric rate (typically around .15 per KW after you figure in all utility charges) now, multiply by the # of hours you operate the lights will give you per day cost. Times 31, per month cost, etc.

If I use the 11 cents you gave an example of. If you have 1 250W MH, with the ballast, you're looking at around 275-300W depending on ballast effeciancy. A 250 MH will cost around 3 cents per hour/ 30Cents per day (10hrs), $10per mo, $120per yr.

I have a 3' fixture. 500W MH plus 78watts of T5 Actinics. W/ballasts, we'd be around 650W. this would =$355/yr @ .15 per kw hr. Led would cost around $120/yr to run. I'd save $240 with out figuring savings from not needing as much cooling!!

Their wedsite says a 3' fixture would cost $1900. With just the savings in lighting electricity, I'd pay for the fixture in 8yrs.

If I change my MH's and T5's once a year, that costs around $250/yr. Add that into the equation of lamp savings and lighting only energy savings, I'd pay the fixture off in 4yrs ($240 energy/yr + $250 lamps/yr) Again, now you could figure out your energy savings on not using the chiller!

There! Being an electrical contractor, I get asked about energy savings all the time. I did this quick, but it should be accurate. Hope this helps! Tim

P.S. As you mentioned, I also do not know the cost or what's involved in replacement of the LED's in the future. I only know they rate this fixture at 50,000 hrs, which is 5.7yrs.


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Old 10/28/2007, 10:46 AM   #39
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Oh, By the way...Easiest way to figure out your KW rate per hr, because of all the other supplier charges, etc.....Take your electric bill and divide by your KWhrs. In Western MA, I'm paying 15.8 cents per KW/hr. Tim


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Old 10/28/2007, 01:36 PM   #40
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The like the electrical calculator here:

http://www.reefcentral.com/calc/tank_elec_calc.php

I am at approx $75/month.


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Old 10/30/2007, 02:45 PM   #41
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The AI unit is modular ( comes in 1 foot sections ) and the leds themselves are easy to take out and replace ( i had to open mine up to remount something that moved in shipping ). Overall, I'm really happy with it so far, but it's only been a few days so I can't say too much just yet. But like I said, very happy so far. Watching the sunrise and sunset is just too cool!


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Old 10/30/2007, 07:22 PM   #42
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Quote:
Originally posted by k9cop1512
Oh, By the way...Easiest way to figure out your KW rate per hr, because of all the other supplier charges, etc.....Take your electric bill and divide by your KWhrs. In Western MA, I'm paying 15.8 cents per KW/hr. Tim

Not all locations have a flat rate utility rate. Most of California, for example, is on a tiered rate structure. For the fist 100% of baseline each month the rate is .12, for the 101% - 300% the rate is .25 for everything above 301% the rate is .37. The baseline is just a few hundred KWH. In the 5 years we have lived in our current house (even before installing our tank) we always hit the 3rd tier each month. The utility rates should be listed on your electrical bill (I thought that was a Federal regulatory law these days, but I could be mistaken ?)


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Old 11/12/2007, 09:05 PM   #43
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Whats with the watts?

I have always wondered why hobbyists focus on watts. The real question is whether the coral is getting enough light - lumen. At sea level, the sun provides about 2650 lumen per square foot.

The other is PAR - you need 1800 microMol/m2/sec. Any quantum meter will show you. You have to be careful about lights that achieve high PAR by boosting the violet/blue spectrum at the expense of the rest. A balanced spectrum is needed.

You can define better or worse balanced spectrum by looking at the CCT. The CCT of many high Kelvin MH are around .26 X .26 which is too far away from a balanced spectrum. Certain deeply growing corals will do fine, but it makes it tougher to raise a larger range of coral.

A CCT of about .31 X.31 is more appropriate when you have corals that normally grow in a wider range of depths.


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Old 11/12/2007, 11:50 PM   #44
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Quote:
Originally posted by jcltok
I have always wondered why hobbyists focus on watts. The real question is whether the coral is getting enough light - lumen. At sea level, the sun provides about 2650 lumen per square foot.

The other is PAR - you need 1800 microMol/m2/sec. Any quantum meter will show you. You have to be careful about lights that achieve high PAR by boosting the violet/blue spectrum at the expense of the rest. A balanced spectrum is needed.

You can define better or worse balanced spectrum by looking at the CCT. The CCT of many high Kelvin MH are around .26 X .26 which is too far away from a balanced spectrum. Certain deeply growing corals will do fine, but it makes it tougher to raise a larger range of coral.

A CCT of about .31 X.31 is more appropriate when you have corals that normally grow in a wider range of depths.
Translated: "I just found reef central"

I think you can rest assured that everyone in this thread knows what you have posted already... you pretty much just walked into the car dealership and told the salesmen what kinds of cars they sell with that last post. Wattage does concern us though as far as what we spend on our utility bills. Being that large reef tanks are using more and more wattage, keeping track of how much we are spending on our reefs as far as upkeep is important.

Here are some websites that may bring you up to speed on where we are at...
http://www.reeflightinginfo.arvixe.com/

...Sanjay has also written a series recently, to fill in the blanks for anyone who didnt already know...
http://reefkeeping.com/issues/2006-02/sj/index.php

http://reefkeeping.com/issues/2006-03/sj/index.php

http://reefkeeping.com/issues/2006-04/sj/index.php

http://reefkeeping.com/issues/2006-05/sj/index.php

As you will see from that last article, your suggestion of a CIE chromaticity (not CCT) of .31x.31 isnt on the market. And CCT is something different, not given by coordinates like you gave.

You will also find that you suggestion of "2650 lumen per square foot" isnt a measure you can use. Lumens are used to give the total output of a bulb, its not used to describe light across a surface... that would be Lux or Footcandles. In reefing, we tend not to use the photometric scale though since its not an accurate measure of radiant energy. So we stick with PAR, or PPFD. 2650 lumen per square foot isnt really a guideline we can use, neither is 1800MicroMol/m2/s. At what point should we have 1800? At the bulb? At the water surface? At the coral? In nature, you get over 2000 at the surface in Hawaii in the middle of winter. The amount we put in our tanks should be much less than this though, at the surface, since our tanks are not 30' tall like in the ocean. If our tanks were getting 1800 at the surface, our corals would be killed, since our corals are from waters that are 5-25m of depth usually in the wild, and are used to intensities often no more than 300-400 (max of 700 for some yellow porites). So its not like anyone needs '1800'... Many tanks have PAR levels of over 2000 near the bulbs if halide (very concentrated light output), or 900 if a tube (T5s). These levels drop off to less than 1000 at the water surface usually, unless you have a very tall tank and need very intense halides (400s) to penetrate to the bottom. Under the surface, light levels usually are 500-600 at most in the first few inches under the water, and often 200 or less at the sand. So where are you getting this '1800' from?


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Old 11/13/2007, 11:54 AM   #45
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hey sanjay, love ur site

have u ever tested the ratings on powerpaq 14k
they come w/ the current USA SunPod 1x150W HQI
Fixture


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Old 11/15/2007, 07:30 PM   #46
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Hahnmeister

You state “I think you can rest assured that everyone in this thread knows what you have posted already... you pretty much just walked into the car dealership and told the salesmen what kinds of cars they sell with that last post.” With no malice intended, I guess it would be useful to provide some information for the car salesman. Sorry, JUST couldn’t avoid saying that. It is truly with positive intent that I suggest the following.

You state “As you will see from that last article, your suggestion of a CIE chromaticity (not CCT) of .31x.31 isn’t on the market. And CCT is something different, not given by coordinates like you gave.” Dominant wavelength is derived from the CIE 1931 Chromaticity diagram and represents the perceived color. CIE1931 was the panel that established standards in the year 1931, and CIE ratings are based on CCT coordinates. Attached is a manufacturer’s chart for CCT for LEDs. The bin number is to be able to order the product item you want. Note that particular CCT coordinates indicate different Kelvin. Consider what the coordinates are for a 20,000 Kelvin light source.

I have to attach the file to a separate post since the size of the file is to big!

You state “Lumens are used to give the total output of a bulb, its not used to describe light across a surface... that would be Lux or Foot candles.” Well… a foot candle is the same as a lumen – 3 foot candles is equal to 3 lumen. I stated “The real question is whether the coral is getting enough light - lumen. At sea level, the sun provides about 2650 lumen per square foot.” I am not suggesting anywhere that 2650 lumen be used at water level in a tank. If you search my other posts, you will find I suggest lower lumen levels for a tank. I simply provided 2650 lumen as a reference point of what the sun does.

You state “So we stick with PAR, or PPFD. 2650 lumen per square foot isn’t really a guideline we can use, neither is 1800 MicroMol/m2/s.” My point was “You have to be careful about lights that achieve high PAR by boosting the violet/blue spectrum at the expense of the rest. A balanced spectrum is needed.” For clarification I mean that high PAR can be achieved but by loading on violet/blue light and not paying sufficient attention to the rest of the spectrum. You have to look at PAR combined with light brightness (Lumen) to create a better aquatic environment. I am sure you have seen high PAR ratings which produce very dim lights. The light output does not provide enough spectrum or lumen to other corals that live higher in the water column.


Your statement of PAR drop-off is correct since there is an inversely proportional relationship between light and distance. You raised this question and I do not know what or how I should respond, but I will it a try based on what I believe you are trying to point out. I repeat – I do not suggest 1800 MicroMol/m2/s at water level unless you have Elkhorn coral or similar ones that live right at the surface. The amount of PAR you get at different levels within your tank is dependent on the output and distance of the specific bulb from the water. Please direct me to the peer reviewed research that specifies “max of 700 for some yellow porites”. The amount of PAR needed at any depth of a tank is dependent on the needs of the coral in that particular tank. John H. Ryther from the Woods Hole Oceanographic Institute did academic research on plankton. Given that plankton have the same kinds of algae (Cholorphyta and zooxanthelle) as corals, he found that "Saturation intensity of Cholorphyta and diatoms for photosynthetic purposes was reached at 500 to 700 foot candles (foot-candle = lumen/square foot) and for dinoflagellates at 2500 to 3000 foot candles. Photosynthetic activity for dinoflagellates (zooxanthelle - algae also) was reduced by 20 to 30% at intensities 1000 foot candle higher". Ryther however, did not specify depths at which photosynthetic inhibition occurred. I believe this data came from laboratory research.

You state “Many tanks have PAR levels of over 2000 near the bulbs if halide (very concentrated light output), or 900 if a tube (T5s). These levels drop off to less than 1000 at the water surface usually, unless you have a very tall tank and need very intense halides (400s) to penetrate to the bottom. Under the surface, light levels usually are 500-600 at most in the first few inches under the water, and often 200 or less at the sand. So where are you getting this '1800' from?” The PAR level of 1000 at water level is accurate in my survey of light output. MHs are raised to avoid heat transfer and so the PAR and lumen output drop significantly. As an aquarist, that should really matter because the advertised PAR or lumen is not what you are getting at the water level. A quantum meter costing $US200 to measure PAR costs would help identify exactly what PAR you are getting and I strongly endorse it as a useful instrument. As to where I am getting the 1800 MicroMol/m2/s, it comes from taking the “perfect” conditions (2000 MicroMol/m2/s) that you refer to at sea level and account for haze and cloud cover: http://www.wsws.org/articles/1999/jun1999/pollj30.shtml) and (http://earthobservatory.nasa.gov/Study/ArabianSea) to arrive at 1800 MicroMol/m2/s. It really is more like 1700 MicroMol/m2/s, but I found many lens use to protect the bulb reduce output, so I propose 1800 MicroMol/m2/s to be safe.

Please feel free to raise any other questions regarding my posts as I do enjoy talking about lighting.

Regards,


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Old 11/15/2007, 07:36 PM   #47
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CCT File

I could not upload the file, so here is a link: http://www.lumileds.com/pdfs/DS56.pdf

Regards,


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Old 11/16/2007, 01:27 AM   #48
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Please direct me to the peer reviewed research that specifies “max of 700 for some yellow porites”.

Dana Riddle 2007. It took the most light of any of the corals he tested. Many others only took a fraction of that. The only organism that was higher (not saying higher light corals dont exist, only that they arent imported) was the crocea clam... it could take whatever you gave it.

As for the exact light output your home reef gets... it all depends on what you want to keep and how tall your tank is. The light levels at the bottom of a tall tank with 400 watt halides could be replicated by a 108 watts of T5s over a 10" tall frag tank. The light at the surface of the tall tank might be 700-900, and at the top of the frag tank, only 300... but in both cases, where the coral is at can still be 200. Thats why I found your suggestions ill-advised.

The other thing to keep in mind (not aiming this at you) is that our home aquaria are usually constant intensity over the course of the day. So calculating MegaMol/m2/day is what you have to do when comparing to nature. A constant intensity of 700 over 8 hours might equal the varying intensity that peaks at 2000 over the course of 11 hours. Comparing corals to what they get in nature seems to be a futile thing though... photosynthesis is all about a balanced chemical equasion. Due to lack of phytoplankton, flow, and other things... this rate will not be similar to what is in nature, so trying to match the light output isnt always the best thing either.

Most of the corals we keep are from 5-20m of depth where the PAR levels drop off very fast. Dana was nice enough to send me a full rundown of daily exposures w/ regards to depth of Corals, microMols/m2/s as well as MegaMol/m2/day. As it turns out, Im clearly overexposing my corals in captivity, yet my daily exposure is lower than what these corals most likely got in nature.

Lumens per square foot... why not just use the term 'foot candles'? Thats what it is. Its like calling a Newton a Kilogram-meter per second squared. Sure they are both right, but no need to make it more complicated.

I dont agree with this though...
"My point was “You have to be careful about lights that achieve high PAR by boosting the violet/blue spectrum at the expense of the rest. A balanced spectrum is needed.” For clarification I mean that high PAR can be achieved but by loading on violet/blue light and not paying sufficient attention to the rest of the spectrum. You have to look at PAR combined with light brightness (Lumen) to create a better aquatic environment. I am sure you have seen high PAR ratings which produce very dim lights. The light output does not provide enough spectrum or lumen to other corals that live higher in the water column."

PAR is the radiometric scale... what is important for corals and photosynthesis (they dont need to 'see', they just absorb the radiant energy). The photometric scale is not as accurate because it doesnt register blue as well... because the scale is based on what the sun makes as well as what our eyes see. But Radiometric meters dont 'boost PAR' by reading the blue levels unfairly... if anything, they are more fair than the Lux meters, since they are not going by what our eyes see... they are going by what the coral sees. I dont get where this comparison to the photometric scale comes from. PAR is the least 'skewed' measure for light around... it measures actual radiant energy, it doesnt measure it unfairly. Do you think photosynthetic organisms give a hoot about how we see the light? Not one bit. And since blue light contains more energy than red (shorter wavelength), it is important for us in this hobby to keep track of it with a PAR meter more than a Lux meter. Blue light can photoinhibit corals much worse than a warmer wavelegth. PAR, in most cases, is really all that matters.

PAR w/ regards to PUR might be worth comparing though. Dana has mentioned that perhaps his earlier review of the Solaris LED's, and putting a high value on the comparatively higher PUR:PAR ratio of the LED's vs other lights may not be the best thing. Too much PUR and too little PAR means the coral may not pigment in very well.



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Old 11/16/2007, 12:40 PM   #49
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I think this where the confusion lies:


"Radiance flux (ФЄ) is the energy per unit time (dQ/dt) that is radiated from a source with the range of .01 to 1000 μm4, which includes the visible, infra-red and U.V regions. A radiant flux of 1 watt means that the source produces 1 joule of energy per second."

So radiance flux measure a WIDE range of energy that is not good to or useful to coral photosynthesis. I have no interest in the visual aspects of light when I speak of lumen - I focus on the photosynthetic range which also happens to be 400nm to 700nm.

PAR meters - "Quantum sensors measure light energy at the specific wavelengths plants actually use for photosynthesis. All quantum meters measure Photosynthetic Photon Flux (PPF) as µmol 2m-s for Photosynthetically Active Radiation (PAR) in the range of 400 to 700 nm. The meter approximates radiation between 400 and 700 nanometers(PAR) as umol m2-s."

Mind that you can fool a PAR meter by loading on one wavelength. It is unethical but it is being done.

I hope this helps the discussion and explains why I suggest PAR and good Lumen/Lux meters for measuring what light is getting to the water. To me what is being radiated is not important if by the time it gets to the water, it is minimal amounts of energy - there are so many variables that radiance cannot be applied consistently (2 units produce the same radiance, but one is hung 12 inches above he water and the other is hung 18 inches - same amount of radiance but different impact at the water).

What is important is what is happening at the water. Let me also clarify that I do believe different corals need different PAR and lumen - I just haven't seen academic research showing the PAR requirements for each type coral.

I am sure Dana Riddle lives up to his reputation and would urge him to publish in the academic world so we can all see his methodology and analysis. With his experiments, Marine Biology would gain much.

Regards,


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Old 11/16/2007, 01:14 PM   #50
jcltok
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Hahnmeister

Can you give me the reference information so I can find Dana Riddles research. Thanks I appreciate it!

You state: "As for the exact light output your home reef gets... it all depends on what you want to keep and how tall your tank is. The light levels at the bottom of a tall tank with 400 watt halides could be replicated by a 108 watts of T5s over a 10" tall frag tank. The light at the surface of the tall tank might be 700-900, and at the top of the frag tank, only 300... but in both cases, where the coral is at can still be 200. Thats why I found your suggestions ill-advised.

Hahnmeister - what suggestion? One suggestion I made to another poster on another thread about how much PAR to aim for was based on the work of John Ryther from the Woods Hole Oceanogrphic Institute. Is that the thread you are referring to?

By the way, what is the PAR of 108 watts of T5s (brand please and model number) at what distance from the water? I am sure everyone will appreciate that information!

You state: "The other thing to keep in mind (not aiming this at you) is that our home aquaria are usually constant intensity over the course of the day. So calculating MegaMol/m2/day is what you have to do when comparing to nature. A constant intensity of 700 over 8 hours might equal the varying intensity that peaks at 2000 over the course of 11 hours. Comparing corals to what they get in nature seems to be a futile thing though... photosynthesis is all about a balanced chemical equasion. Due to lack of phytoplankton, flow, and other things... this rate will not be similar to what is in nature, so trying to match the light output isnt always the best thing either."


PAR is not cumulative. PAR is how much light is reaching the coral at this moment in the span of one second per square meter. The light is there or not there. So, why is measuring MegaMol/m2/day useful - I do not understand?

Regards,


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