Lighting Website Updates

[jcltok]

I have to apologize to you - I reread my posts and I did say "you need 1800 uMol/m2/sec". That is not correct - PAR levels should be set depending on the needs of the coral in the tank! So, I understand why you disagree and I did make a mistake.

Regards,

[hahnmeister]

"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?"

I never thought it was either at first... but I suppose so! Its mentioned in Sprung/Delbeek's last volume (3) in the lighting chapter as well. The daily photoperiod is what is important to the corals. Most of the info Dana and I have talked about has been MegaMol/m2/day. It took some getting used to for me as well. It makes sense though... photosynthetic cells are alot like solar systems and batteries all in one. They 'charge up' and convert radiant energy to the energy the organism needs, as well as for chemical conversion processes for physical mass buildup. So corals are a bit like batteries (plants are as well), and when you look at it like this, yes, the daily photoperiod is what matters. There are limits... like putting a coral under more light than it can handle will just overload its defenses and it will bleach, and putting it under too long of a photoperiod will disrupt the corals night process... but lets say you have a coral that gets 6 hours of light at a PAR of 300, or 9 hours at 200... its the same thing in the end. The higher intensity might cause for more pigmentation to develop to protect the coral (or sometimes this happens in reverse because the light part of the photosynthesis is more than the other energy sources and an imbalance is produced), but thats about it.

If you like PM me your email and I can send you an interesting file of info I asked him for.

[hahnmeister]

Between these posts, and the one on this page...

http://reefcentral.com/forums/showth...7#post11197257

You need to quit posting as if you know more than you really do. You need to read Sanjay's articles, and consider this: what you think you know may be wrong... very wrong. Im shocked nobody else has jumped on you about this, but you arent helping anyone, and if anything, are steering them down the wrong path. You obviously are new at this, and trying to process information without understanding it 100%. So passing along information that is incorrect seems to be a problem. A university level course on the EM spectrum and optics would be my suggestion as well because some of the calculations that you are arriving at are impossible to get with your methods.

I am willing to help, but you have to just stop. You are spitting out more incorrect info at a time than I can possibly type a correction to.

[jcltok]

You asked I stop posting - why don't you go read Dana Riddle to whom you refereed me to. You will find that his and my points though stated differently and coming form different base point to the same out comes. I suggest you listen to yourself before you write. Go reread Riddle and learn some things.

[jcltok]

Just how much data do I have to provide for you to listen. Maybe a Physics Professor from the University of Arkansas can explain to you:

You state: "There is no way you can convert lux to PAR/PPFD... you are talking two different things! You need to stop posting bad info. Also, you can not use a meter like that to get a lumen or PAR per watt figure!! It just doesnt work like that. There are reflectors in involved with what you did, so the intensity will vary with position. Lumens per watt calculations need to be done without a reflector, and are done by calculating the total incidental light from every angle around a light source, not by taking any spot readings. It can be determined by a point reading sometimes, if you know what your total area is and how it varies over that area, but you need integral calc to determine this ratio then.

You need a physics course on optics and the EM spectrum. Seriously... your info is just not right. You arent helping anyone.

Im shocked that Bean hasn't jumped on you already."

Here it is...

Date: Mon Jul 31 16:38:51 2000
Posted By: Jeff Robertson, Faculty, Physical Sciences, Arkansas Tech University
Area of science: Physics
ID: 964457090.Ph
________________________________________
Message:

Light measurements can be complicated but illuminating...

Photometric units, illuminance:
Footcandle = one lumen per square foot. The 16th General
Conference on Weights an Measures (CGPM), Oct. 1979, decided that the candela is the luminous intensity of a source emitting monochromatic radiation of frequency 540 x 1012 Hz and radiant intensity 1/683 watt per steradian. This corresponds to 683 lumens per watt of radiation at approximately 555 nm wavelength, which is near the maximum of the standard photopic spectral luminous efficiency curve.
Lux = one lumen per square meter.

Quantum units, photon flux density:
Microeinstein per second and square meter (µE m-2 s-1). The
einstein has been used to represent the quantity of
radiant energy in Avogadro's number of photons and also
Avogadro's number of photons. The second definition has the
einstein equal a mole of photons, While commonly used as a
unit for photosynthetically active radiation (PAR),
the einstein is not an SI unit.
Therefore: microEinsteins per m2 per second is identical to
micromoles per m2 per second.
(1000 µE m-2 s-1 = 1000 µmol m-2 s-1)
Micromole per second and square meter (µmol m-2 s-1). This term is
based on the number of photons in a certain waveband incident per
unit time (s) on a unit area (m2) divided by the Avogadro
constant (6.022 x 10e23 mol-1). It is used commonly to
describe PAR in the 400-700 nm waveband.

The approximate conversion factors given below will help to
convert absolute energy units or irradiance units (PAR)
as recommended by the plant scientist into illuminance
or photometric values (lux).

Radiometric PAR - Photometric
Source* W m-2 µE m-2 s-1 fc lux

HP Sodium 1 5 33.5 360
(400 w) 1 6.7 72.3
1 10.8

Metal Halide 1 4.6 29.6 319
(400 w) 1 6.5 69.5
1 10.8

Mercury 1 4.7 30.8 332
(400 w) 1 6.5 70.0
1 10.8

CW Fluorescent 1 4.6 34.2 367
(215 W) 1 7.44 80.0
1 10.8

To convert from either W m-2 or µE m-2 s-1 to photometric units, multiply by the appropriate factor." Here is the hyperlink: http://www.madsci.org/posts/archive...36947.Ph.r.html

SO TO REPEAT The approximate conversion factors given below will help to convert absolute energy units or irradiance units (PAR)
as recommended by the plant scientist into illuminance
or photometric values (lux). That is what you specifically said could not be done.

Charmed by your graciousness!

[jcltok]

Hahnmeister

By the way here is a hyperlink to show illuminance conversions for the things you say can't be done:

http://www.onlineconversion.com/illuminance.htm

[NewSchool04]

Wow, this is a very interesting conversation! I'm learning a lot in a round about way for an old History major!!

I had a ? that I hope either of you could answer. I run 3 400W Reeflux 10K bulbs on Coralvue E Ballasts. I shut each one of the lights off for one hour, 1/2 hour apart mid day in the light cycle. Left off, 1/2 hour later middle off, 1/2 hour later left on, far right off, 1/2 hour later left and middle on, far right off, and then 1/2 far right on.

I've heard that this gives the corals a break and allows them to regenerate. Am I wasting my time with this?

Thanks and I hope you both continue this discussion. It's very interesting!

[hahnmeister]

"why don't you go read Dana Riddle to whom you refereed me to"

Because it wont tell me anything needed for this 'argument'. Dont get me wrong, Im not saying I know it all, just that I know what things are wrong with what you posted. You told someone that UV exists at both ends of the visible spectrum... just beyond 700nm/red and right before 400nm/purple. Uh... the 700+ range was Infra Red last I looked. If you cant pass the 9th grade, theres no use talking about the SAT's... know what I mean?

You posted:
"Just how much data do I have to provide for you to listen. Maybe a Physics Professor from the University of Arkansas can explain to you:"

Its not a matter of how much. You can post as much as you want, but if its not correct, it doesnt make a difference.

That professor is not correct, at least not in our context. It seems in that case, he is talking about a fixed spectrum (as in, for land plants), so a relative conversion is possible. This is the only circumstance that you can compare PAR to Lumens, and only in a relative aspect at best. Its like asking how much diesel you can use to replace unleaded gas in an engine and get the same power... it just cant be done. Sure, there are relative comparisons for horsepower and torque based on the engines you use these fuels in, but you cant compare them directly.

PAR takes the raw photon count per an area... raw visible radiant energy (radiometric scale). It wouldnt make a difference which planet you are on, or what species you are (how you percieve the light), the PAR would be constant. The photometric scale is scaled to what our eyes see. Its the total photon count, but the blue is only counted at 10%, the green at 100%, and the red at 85% (I know those numbers are not exact, but off the top of my head, thats pretty much what its like). Its because our eyes dont see blue light (only 10% of our cones are tuned to see blue in daylight conditions), so having a very blue light might make it seem very dull to us (or in the photometric scale), yet to a coral, which is more than likely primarily depending on blue light in the first place... it could be very bright.

It may seem extreme, but to convert PAR to lumens is something like asking this: "how much red light does it take to equal a given amount of blue light?"... as if there was some way to keep adding red light until you get blue or something. It just doesnt work like that.

So a 10,000K bulb that looks very bright to us may have a PAR of 400 w/o a reflector at 12", and the matching lux rating might be 800 (unitless ratio number). But lets say you have a 20,000K bulb with a PAR of 400 at 12" w/o reflector... one with a huge 460nm blue spike. Well, a lux meter isnt going to pick this up so well, so it might register at 400 only, even though the PAR is the same. To the coral, what we cant see as well (blue) means very little. In fact, bluer light (shorter wavelength, higher frequency) contains more energy (and needs more energy to produce) than longer wave light (red uses less than green, green uses less than blue). And UV is even harder to make (contains more energy). If you read Dana's articles, you will see how he talks about UV photoinhibition alot... he covers it pretty well. But in the same respect, you could have a coral under 200 micromol/m2/s of light with a daylight spectrum and it could do just fine, but if you switch to a primarily blue bulb of that same 200 micromol/m2/s you could end up photoinhibiting (burning) the coral. This is also why bluer halide bulbs tend to have lower PAR than daylight bulbs... bluer light takes more energy to produce.

So its not that manufacturers are manipulating PAR readings by boosting the blue spectrum. Most mfg's give lumen ratings anyways for their bulbs, so trying to manipulate these readings by creating artificially high blue spikes wouldnt do them much good, as the photometric scale doesnt pick it up as well.

If you want, I can go around to all your posts, quote every piece of untrue info, and we can deal with it one on one to get you on the right track.

[hahnmeister]

Originally posted by jcltok
Hahnmeister

By the way here is a hyperlink to show illuminance conversions for the things you say can't be done:

http://www.onlineconversion.com/illuminance.htm

Lol.... yeah, you need to check your own info there. Notice that there are no conversions from any photometric units to radiometric units. There is no conversion from PAR to lux, or PPFD to lumens, because it doesnt exist. Its old news on this forum... really, stop embarrassing yourself.

[hahnmeister]

Here is a list of the 'bad info' you have posted...

1.

Originally posted by jcltok
I agree with all of the suggestions - since we do not have first hand information of your corals' needs.

In terms of lighting, consider whether they are getting enough light - enough lumen - you need about 15 per square inch. Next is spectrum - is the light covering the 400nm to 700nm in a balanced way? Finally, is there enough PAR - 1200 micrMols/m2/sec is the right amount.

and the correction you made doesnt help...

Originally posted by jcltok
oops. I intended to say 1800 microMols/m2/sec of PAR.

2. In this thread:

Originally posted by jcltok
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.

3.

Originally posted by jcltok
What is the depth of a 30 gallon tank? Light output is inversely proportional to distance. If your tank is less than 2 feet tall, then I suggest about 1200 lumen per square foot.

Watts are not the important question - the real question is how much light are you getting at water level? A bulb may be more efficient at turning electricity into light, so watts are not a useful guide.

Second question is what is the PAR. Better PAR with a balanced spectrum produces a better aquatic environment.


Heat from the lights is likely to be an issue with 30 gallons - make sure you find a way of getting that heat away from the water.

4.

Originally posted by jcltok
...1. You replace 175 w MH bulbs every six to eight months due to phosphor degradation. Using $75 for each bulb as an average, and having two bulbs in one hood, means $300 a year more or less. 2 96w Actinics at $30 each every six months adds $120. You are now spending around $420 just for the bulbs annually.

5.

Originally posted by jcltok
By the way, the sun produces 1800 microMols/2m/sec of PAR. So the fluorescents at 200 to 350 PAR are a little low compared to 1800.

6.

Originally posted by jcltok
I am not a physicist, but as a manufacturer of LED lighting, I can respond to your statements and questions.

...3. You seem to confuse PAR with light output. They related but not the same. Light output is based on lumen and can be measured by a lux meter and then converted to lumen. You can also use a lumen meter to measure if the instrument has that function.

4. PAR has been used in reef lights because of research by Ryther at Woods Hole Oceanographic on plankton showing the lighting needs of the plankton algae which happen to be the same species of the symbiotic algae found in stony corals. PAR, measured with a quantum meter, should measure the output of evenly distributed 400nm to 700 nm wavelengths. PAR has been manipulated as you state. Many MH manufacturers add exceptional amounts of violet/blue phosphors at the expense (lack) of other wavelengths, to manipulate the quantum/PAR meter into reading higher PAR.

5. PAR manipulation success depends heavily on the ignorance of users and their unwillingness to publish even their manipulated PAR results. Why? Because sea water level PAR should be about 1700 microMols/m2/sec and the manipulators are putting out maybe 300 or 600 PAR. The PAR of LEDs can also be manipulated by adding more blue color LEDs and minimizing the count of white LEDs. The same logic applies to adding phosphors to MH to manipulate PAR. That is why you see deep blue but very low light LED fixtures. The trade off is lower manufacturing costs, higher Kelvin ratings and faint light.

6. Lumen out put at sea level is 2600 lumen per square foot or 18 lumen per square inch. Lumen and PAR should be measured at the water level, and not at the source. The reason is that light output is inversely proportional to the distance it travels - the farther the light is, the dimmer it is. So high lumen - brightness is necessary. MH will reduce their light output and change spectrum very quickly which is why they should be replaced every six/eight months. LEDs if kept at proper operating temperatures, do not change lumen or spectrum until after 30,000 hours - assuming you buy the best product.


7. Kelvin ratings are a measure of COLOR COORDINATE TEMPERATUREs which can be measured by instrumentation. Higher Kelvin does not mean better PAR. Higher KELVIN means bluer light. Why is this relevant? Because corals grow at different depths and some grow in the violet/blue light - hobbyists think that is what they need and it looks cool! Unfortunately many corals live in a higher water level and do not get the spectrum they need. Also actinics make corals fluoresce and therefore leads people to bluer lights.

10. Spectral graphs are provide in "relative output" - in other words the proportion of one wavelength in comparison to others. In high Kelvin MH you see a huge spike in blue and minimal in the rest of the spectrum. In LEDS, you can expect a spike in the blue, a dip in the 475nm range, a rise in the 500nm tapering off to near infrared. (700nm). LEDs are not the perfect solution either - they happen to be better than MH and Fluorescents. Keep in mind that what I have stated above assumes the best LED available and not just any LED. I have not stated which LED is best on the basis of published data because that is not appropriate in this forum! I can be reached at jcltok@cox.net

7.

Originally posted by jcltok
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,

And then everything you have posted here since.

[hahnmeister]

1. Those numbers are meaningless.

2. Still meaningless. Like saying 'you need 2000 calories'. Huh? For what? Per day, per hour? In this case, the light that may happen in nature at the water surface is a useless statistic for our captive systems. Only very large public aquaria actually need lighting that creates intensity at the surface as high as in nature. Most of our tanks have intensities that are a fraction of that because the light innt penetrating 5-25 meters!!! Its going 4-24" usually. So to tell people that they need some 'golden number' like 1800 whatever is completely useless, and false. Every tank will have different ideal intensities at the surface depending on the height of the tank, and the spread of the light source. For instance, a PFO mini-pendant halide can have a hot-spot of over 2000 at the water surface right under the bulb. Then, that same bulb, just as far from the surface in a lumenarc style reflector might only have a peak reading of 1200 at the surface. Yet, if you go down into the tank 2', the lumenarc will be more intense... how is that? You should look into dispersion fields, optics, and the inverse square law to correct this.

3. same as above really.

4. halides dont contain phosphors. 175s can last alot longer than that as well.

5. The sun produces 1800 where? And what does that have to do with the price of cottage cheese in China? And to say that T5s or other phosphor based bulbs with their PARs seem low it completely misunderstood and innacurate. There are plenty of T5s that can give halides a run for the money. The difference is that T5s and other tube bulbs are more spread out... so you will get a higher reading close to a halide bulb than you will a phosphor/tube bulb because the source is more concentrated with a halide. In order to compare them with accuracy, you need to measure them at greater distances without reflectors.

6.3, no that person was not confused... PAR is visible light output. Usually it is given from 400-700nm, just like the photometric scale. Shame on you for now telling them they were confused when you were the one who was/is.

6.4, you cant manipulate PAR like that. PAR, as you stated yourself, is a pure measurement that is evenly distributed. So a bulb with high amounts of blue will not give a 'manipulated reading'.

6.5, rubbish, just rubbish.

6.6, more meaningless stuff.

6.7 Kelvin ratings are not coordinate temperatures. They are arbitrary numbers for marketing. You are talking about the CCT. you will also find from the multiple spectrum graphs that Dana and Sanjay have published that red light drops off rapidly under water, even at just 5m. And then green as well. Since most corals we keep are from 5-25m depths, keeping them in bluer light is right on the money.

6.10, spectral graphs provide absolute outputs. See those numbers on the left hand side of the graph... those are actual exact amounts of radiation. They are not 'relative amounts' as you say. PAR/PPFD, for instance, is the integral of a spectral graph (a measure of the area under the line from 400-700, or 300-800 for extended range, for a total output).

I was unaware that LED's had problems with 475m light... that is blue light (450-495) by the way. Many LED's have this spectrum.

7. "I have no interest in the visual aspects of light when I speak of lumen"... thats just plain funny right there. Im holding my gut in. You pretty much just said "I have no interest in how many miles per hour Im going when Im talking about speed"...lol. Maybe you dont concern yourself with the visual aspects, but the lumen scale IS exactly that... lol.

Oh, and you cant 'fool a PAR meter' by loading up on one spectrum. Who told you that? Sure, a bluer light will have a higher relative PAR to lumen ratio than a warmer light, but thats not a form of manipulation. Its the true reading (unless its a crappy Quantum meter that has a faulty pickup at some wavelength, but thats not the radiometric scale were talking about then.

"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."

Okay... like I said... have you even heard of Dana Riddle? He has been publishing here (www.advancedaquarist.com), almost every month or so, on spectrum, intensity, etc.

http://www.advancedaquarist.com/sear...ct=Dana+Riddle

You pretty much just walked into the Harley dealership and commented that you dont see any motorcycles with that one.

And then there is everything in this thread that I have already commented on.... like how you cant get a total efficiency rating of a bulb with your methods (I cant even do that... its so hard to do its not even funny... special room, equipment, computers).

[hahnmeister]

Now, for the REAL info that you might like...

PAR at depth, as per emails with Dana (thanks Dana, you rock!):




Thats why 'daily amouts' are important. You can overexpose a coral over the course of a day by giving it just as much as in nature... since the peak value only happens for a fraction of the day underwater. What we give corals in our tanks would look not like a bell curve, but a couple steps up, and a couple down, or maybe not even... maybe just a square (lights come on, stay on all day w/o varying in intensity or position, then turn off). So calculating the total is most important.

Then, consider the depth that the coral comes from... a coral that comes from 5m will get alot more light than one from 15m. If you use the top graph, you will see that basing any captive system on what the ocean gets at the surface is useless. What matters is at the coral. In nature, the surface might be at '1800', but only 400 at a coral's depth. Well, in a captive system, the intensity at the surface might only be 500, yet still 400 at the corals depth because the coral is only 6" below the water's surface.

Then there is spectrum as well. As per Sanjay's article here:
http://www.advancedaquarist.com/2005/8/aafeature/view
You will see how light changes very fast as it filters throught water:

(see those numbers on the left... those are actual energy readings, not 'relative' numbers).
So those 'bluer bulbs that try to manipulate the PAR reading by being so blue'... they are just giving the coral what they are used to if they are from deeper water. Thats all.

I hope that gets you on the right track. I hate to see people, esp ones who link themselves to being a mfg of lighting products like you have, to spread bad info. It hurts everyone in the end.

[JCTewks]

Okay, now hahn...are there any bulbs out there that actually produce that sort of spectral plot? Most graphs I've seen have a large spike around 420-460 or so, then nothing of note in the 500-550 (green).

I think if LED's ever get cheap enough there should be a way to swap out actual LED's for a spectrum that mimics that at certain depths in the ocean....then we could TRULY run lighting as the reefs are with variable output and random electronics to mimic clouds and such....that will be a good day! and if we can do it for the price of a budget MH system would be even better

[hahnmeister]

There are LEDs and T5 bulbs that are pretty similar to those curves. With good bulb husbandry, I think those spectrums are easiest to hit with T5s (LED's as well). Halides, not so much... unless you combine a 14,000Kish bulb with 420 and 460nm peaking T5s (blue and actinic). That gets pretty close.

Lucky for us, corals can photoadapt to an extreme extent (like humans adapting to eating tree bark), so as long as we 'try' to get close, they seem to pick up the slack. This 'photoadaptability' is no doubt due to the sessile nature of the coral once grown, but the fact that where it lands as as a 'spore' can influence what spectrums of light it may have to work with. Terrestrial plants can vary in elevation, position, etc... and the light spectrum doesnt vary a whole lot. 5m vs. 30m of depth in the ocean is like two seperate worlds, and that spore of acropora cant really get to be too picky where it lands. Sure, if its in a totally wrong spot, it wont 'set up shop', but beggars cant be choosers.

[fishdoc11]

Here at Reef Central, we believe that dialogs between participants should be conducted in a friendly and helpful manner. If you disagree with a posting, please express yourself in a way that is conducive to further constructive dialog. Conversely, when you post on any given subject, you must be willing to accept constructive criticism without posting a hostile or inflammatory response. Personal attacks of any kind will not be tolerated. Please work to insure that Reef Central remains a friendly and flame free site where everyone, especially newcomers, can feel free to post questions without fear of being unfairly criticized. Thank you for your cooperation.

[kdblove_99]

Sanjay,
The Helio 250W 20K SE bulb is there any info this bulb? If there is i cant find any.

Also quite a few posts back someone had asked if you were or are going to be testing the Lumen bright reflectors?

[DgenR8]

[Antman]

Silly question am I the only one who thinks the XM 20K lamp is NOT blue enough on an Mag 57 ballast ?
I have used the Blueline 14K lamp and it looks great Nice and blue but the Par is in the dumps
The XM is 51 for a 175W and the blueline 14K 250W is only 31

[Rickyrooz1]

How often should I change my 250 watt metal halides? I'm using Phoenix 14K bulbs on I believe a pulse start dual magnetic ballast.

[Rickyrooz1]

hahnmeister, just saw your tank . . . nice set up. Are you running one 250 watt metal halide with T-5's?

[hahnmeister]

Thanks Rickyrooz1,
That is just one 250wattDE on a light rail, yes. I use a ushio 14,000K in it. The thing is, its bright, maybe too much. I did a quick PAR reading the other week (black box, no reflector), and it scored within 5% of my Giesemann 14,500K. I wonder if this bulb hasnt been 'redone' recently or something... I think its too bright for my application. Im going to have to try a different bulb. I love the color with my 4x54wattT5s (2x true actinics and 2x blue+), but some of my corals are doing the 'pastel look'.

I wish there was a '200 watt' bulb or something, as this bulb is already been cut back to being on an Icecap ballast (rather than the PFO HQI). So Im trying to find a duller daylight bulb... but thats sort of a waste. I dont need something bluer though either... but maybe if I made the halide a 20,000K, and put a daylight bulb in for the T5s, it might be alright.

I should have made the tank 4" taller. Im seriously considering switching to all T5s (8-10 x 54wattT5) on this tank. The halide just has too much of a 'hot spot' under it. Some corals love it, but others hate it. Because of the light mover, the tank doesnt really have many 'low light' areas either. So dont take it as the light rail being bad or anything. I might be able to either swap the reflector for my lumenarc DE pendant to spread out the light more, but I might just end up moving down to a 150watt bulb.

[ksed]

Hahn

I currently have 2x250w megachrome marine 12.5k On a 125g 24"high . I have some blue acros. which I thought should be bluer I'm woundering if I need to upgrade to 400w or do you think I'm getting enough par on the 250's to keep some light loving Acros. The fixture is located approx. 9" from the water.
They are on for 9hr a day.
Wow thats intresting on the par of Ushios and the Coral.
Thanks!

[jospears]

Hi Sanjay you have a very nice 500gal tank.

Can you tell me what your light specs are.Also I am going to run xm 250w 10000k bulbs on my tank and could you tell me which ballast do you suggest.


m58
pfo Pulse-start:
pfo Electronic:
ice cap
ice cap electronic
or will the m58 run the bulbs just fine it is a lot cheaper.

Thx in advance

[hahnmeister]

Originally posted by ksed
Hahn

I currently have 2x250w megachrome marine 12.5k On a 125g 24"high . I have some blue acros. which I thought should be bluer I'm woundering if I need to upgrade to 400w or do you think I'm getting enough par on the 250's to keep some light loving Acros. The fixture is located approx. 9" from the water.
They are on for 9hr a day.
Wow thats intresting on the par of Ushios and the Coral.
Thanks!

The 14,500K coral bulbs will be slightly bluer, and have a very decent output.

Regards,
Jon

[NewSchool04]

Originally posted by NewSchool04

I run 3 400W Reeflux 10K bulbs on Coralvue E Ballasts. I shut each one of the lights off for one hour, 1/2 hour apart mid day in the light cycle. Left off, 1/2 hour later middle off, 1/2 hour later left on, far right off, 1/2 hour later left and middle on, far right off, and then 1/2 far right on.

I've heard that this gives the corals a break and allows them to regenerate. Am I wasting my time with this?

anyone have a opinion on this?