HQI

[Bill]

Why are HQI MH lights the newest trend? I'm putting together a new 160 gallon tank and I see HQI everywhere now. What's the advantage over the old mogul based enveloped MH lights?

[Chuck S]

In testing that has been done there is no large advantage over either in fact you should do a search for the latest testing that Sanjay Joshi and Dana Riddle have done. There is no difference. A HQI bulb is simply a mogul bulb without the glass envelope around it. You need to use a protective lense anyway with the HQI so your sticking the glass there just like a mogul. It is simply the newest thing that is an old thing. Sanjay crushed the big HQI bandwagon at the last MACNA conference.

[greg c]

In my experience the HQI reflector comes into play. The HQI may not produce more PAR but most people claim the light spread is better because the mogul end is not there to block light. I haven't seen Sanji's lates test but on previos test the 250 HQI produced more PAR that many 400 watt bulbs.

[Chuck S]

Greg,

At last years MACNA Sanjay put that arguement to rest. A 250 HQI does not put out more PAR than a Mogul. Period. All his latest testing proves such said point.

[greg c]

Thanks for the info, I wish i could have been there. Were can I find the results of his latest test? I last heard from him when he spoke at our club meeting last year, at that time his views were different, although he had not compared the bulbs side by side.

[Chuck S]

I beleive his study is ongoing to my knowledge and his only public acknowledgement was at MACNA. I had the fortune to site down for a long time talking to Dana and Sanjay. There are alot of misconceptions on lighting. There are also alot of revolutionary products being developed so just wait and see.

[greg c]

I'll keep an eye out for the results of this study. Too bad I already bought my lights. Based partially on the comments he made in our meeting. Either way, in CA I can't afford the electric bill for 400 watt MH

[Mojoreef]

Chuck you lost me bud? A HQI has a lens. Or are you thinking about the Double ended version, if that is the case then yes. From what I know on these is that the hqi basically just overdrives the bulbs a little more. Chuck did sanjay mention in his last talk that this extra wattage do anything to drive the par a little deeper inot the tank?


Mike

[tendar]

Here is Sanjays artical on 150 HQI's bulbs and ballasts
http://www.advancedaquarist.com/issues/nov2002/feature2.htm

and here is the link that kind of goes with it on reflectors
http://www.advancedaquarist.com/issues/mar2003/feature.htm

[Chuck S]

Mojoreef we kind went off topic here. Yes HQI ballast is the main topic but a comment was made on the old that people would spread about a 250 watt bulb beating the 400 watt. /ubbthreads/images/graemlins/wink.gif

Tendar thanks for the Links. Too bad Sanjay has not released the testing on the higher wattage lighting. His talk at last years MACNA was wonderful.

[Mojoreef]

Ahhh yea..Thanks Tendar, I have seen that one before. That doesnt not say anything about normal 250's compared to HQI though?? or am I missing something.

[Mojoreef]

Ahh you posted while I posted, lol. Lighting is a fun subject. I have a couple of Hqi DE 250 watts on my tank, and to be honest thier a pain in the but. The glass lens always get covered in creep. Thier is however a noticable difference between the normal 250 and these ones. I use Ushios in both fixtures. anyway my advice is if you want 250 HQI go mogul base the DE are lousy.

Mike

[greg c]

[ QUOTE ]
Ahhh yea..Thanks Tendar, I have seen that one before. That doesnt not say anything about normal 250's compared to HQI though?? or am I missing something.

[/ QUOTE ]
Check Sanjay's web site he has the 250 watt bulb comparison. I bought my lights based on those test results. Unless I read them wrong, he had good things to say about the 250 hqi's. Omegatron was able to talk to Sanjay in person so he may have behind the scenes knowledge of some flaws in Sanjay's test. From my interpretation (which may be wrong) of the results, the 250 hqi outperformed the 400 watt radium on any ballast.

[Bill]

What makes the most sense to me is that the HQI output was compared to the Mogul output and the glass shield around the Mogul cuts it's light output when compared. I suspect that a glass shielded HQI and a Mogul bulb with only it's basic envelope would compare similarly. I'm going to speculate that the HQI pushers can claim higher PAR simply because the basic bulb has no envelope like a Mogul bulb.

[Chuck S]

There arguement is mute cause the mogul bulb is nothing more than a HQI with a glass shield. You can not use an HQI without placing a glass shield on it. There is not a difference when one thinks of it in these terms. Look at the construction of an HQI. It looks the same as the insides of a mogul bulb. Thats cause it is. /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/peace.gif

[greg c]

I want to thank you for your response on this issue but now you got that noodle in my head churning!

I have noticed that you have strong feelings about this issue. I will let you know, I have 250 watt HQI lights so before I go on I want to be up front about this. I have also played around comparing a 400 watt Ushio in a spider reflector vs. my 250 watt AB in a reef optix 3 reflector on a cheapy LUX meter. Now I'm no scientist and from what I have read from your post I must have done something wrong for the 250 HQI (with the UV sheild) to have comparable results with the 400 watt bulb. I can except that I made a mistake becase my test was with less than scientific standards and I did not use precision measuring equipment.

Are you saying that Sanjay came to the wrong conclusion when he tested the 250 HQI bulbs against other 250 watt mogul bulbs?

"If you subscribe to the “more PAR is better” theory, then obviously the best choice is either the double-ended 10,000 K lamp or the 6500 K Iwasaki lamp. If you subscribe to the “more blue is better because corals are found in water where the higher wavelengths are filtered out” theory, then it’s worth noting that the 6500 K Iwasaki lamp had higher output in the violet/blue range than the 10,000 and 20,000 K Coralife lamps. The double-ended 10,000 K lamp is the best combination, offering both the best PPFD and the more blue color many reef hobbyists are interested in."
(taken from the conclusion in "Spectral Analysis of Metal Halide Lamps Used in the Reef Aquarium Hobby Part 3 — 250-Watt Metal Halide Lamps")

Was Sanjay wrong when he made this statement? /ubbthreads/images/graemlins/confused.gif

I found no mention where he warned readers that with the UV shield in place, the PPFD of the 250 watt HQI would be along the same readings as the mogul bulbs. However Sanjay did make this statement:

"The UV output of the various lamps is shown in Figure 5. Comparing the UV output in this chart is somewhat misleading. The double-ended lamp has much higher output thaen the others, but remember this lamp requires a UV filter, which would bring this number down."

But that only states that the UV levels would bring down the UV shield. I only bought the 250 HQI fixtures because they came highly recomended by Sanjay when he visited our club in last year. His statements to you may contradict my views but so far his data doesn't. Once my tank has cycled I will have our club over to measure my light on the club par meter. This way we can compare them with the others who are running the 400 watt Radiums on the HQI ballast. Who knows, by this tme next year, the whole club may be running 250 HQI's.... Well, maybe not. It's hard to pass up the $72 - $75 price tag of the Radiums.

[David Grigor]

Greg,

here is where I think your miss something.

In the previous articles that your quoting from, there are incosistancies. Moguls tested without reflector being compared to DE with reflector but without UV glass.

They say that you'll loose about 20% PAR output when you add the UV protecting glass and you'll gain 20%+ when you add a good quality parabolic reflector to the mogul. Plus the fact that using a Parabolic reflector the highest intensity is not directly below the bulb ( which is how previously tested ) but rather on eigther side of the bulb because of the reflector properties. Note that my percentages in the example may be off but just trying to convey a point.

When you take these things into account the actual real world difference becomes marginal.

Also, I don't like your generalization about 65K having more blue/violet waves than a 10K or 20K etc. While technically this may be true, becasue the 65K has a much higher concentration of the lower yellow spectrum, Please don't imply that you will get the same effect on corals. You will get much different coral coloration results despite simliar output in the blue/violet range.

While I do think intensity is important. It seems you put way too much emphasis on PAR. Remember PAR takes in account the whole spectrum when not all corals may use all the spectrum. So to say one is better than another because of Higher PAR is not necessarily true.

IMO: There is no such thing as a perfect bulb. All corals are different and all corals respond differently to various spectrums so to say one is Better than another you would have to rate a bulb on a coral by coral basis.....

I will go on record saying, Yes I have used 150W DE, 250W DE and well as all the standard MH ( 175,250,400 ) wattages in various bulb spectrums including Iwasaki 65, 10K and 20K. So I am not speaking from what I read but also from what I have experienced.

Also, it has been my experience just the opposite on light spread. I get better light spread from mogul with parabolic reflector than I do from DE with old style PFO mini-pendant and Sunlight Supply Reef OptixIII reflector ( as those are the only DE reflectors I have used ). I know this because I have played with them on my 8', 30" deep tank and quite noticable light spread difference in favor of the mogul.

I also have a LUX meter and if your trying to do tests without the senser and MH mounted in fixed positions you really can't get a good test. I know that even just a centimeter differences in distance can really scew your numbers. Plus you would need to take readings at various points in a wide distribution as the output from the reflectors is not evenly distributed across all data points.

[greg c]

David,

Thanks for the reply. You have a reef tank that I surely envy. You get a hit from me on your website almost daily.

I find nowhere in Sanjay's article regarding the 250 watt bulbs any mention that the HQI DE bulb was tested with a reflector. (in another test he did admit that the 150 watt HQI was tested with the reflector) Sanjay usually doesn't hide facts nor should we assume that a reflector was used. Without UV glass, that is no contest, he clearly stated that there was no UV glass used.

As far as the 20% decrease in par from the UV glass. Who is "they", where did "they" come up with this data.

I understand that you didn't like the comment about the 6.5K bulbs, sorry for that. I'm not sure about that either but that was a quote taken directly from the article. Sanjay does beleive the 6.5 K is the best overall bulb for reef tanks (per his articles). I do agree, with the difference in color that comes from 10K and 20K bulbs vs. 6.5K bulbs. That is why I have always used the AB bulbs.

At no time have I stated that there is a perfect bulb, I took offense to statements that the 250 watt mogul bulb having the same output as 250 watt HQI DE. I have seen the difference and it is significant. Sanjay's testing was used as a basis but I felt the data was being misinterpreted. If I am wrong, I'm sorry for the trouble, but Sanjay's data and conclusion suggest that the 250 HQI DE is the best choice for a 250 watt bulb.

[Chuck S]

Greg,

David brings up many good points. Nowhere in any aticles published YET have we seen some of the results that David and I are speaking of. People got alot of first hand knowledge at MACNA conferences talking to people first hand. I spent a good time talking with many noted people in the field and let's just say the misconceptions people are led to beleive are great. There was speculation for over a year on the boards that a 250 HQI beat 400watt mogul's for along time. What a crock.

I have personally used 400watt bulbs in every spectrum almost and can tell you that each one as David pointed out has its own effect on coral. I am running a 150 HQI 10k on a prop tank and all is well. I personally prefer a mix of 6500K and 20000K.

[greg c]

I appreciate you two debating this issue with me but I think we must separate fact from opinion. I certainly understand that there may have been a misconception to the 250 HQI vs 400 mogul. However these misconceptions have been purely based on Sanjay's previous data. If Sanjay's previous data is unreliable, why should we trust his upcoming data? It seems to me you are putting alot of weight on someones tests, who by your own statements has fed us unreliable data in the past. If this is correct let me know. But if you are contending that Sanjay's previous test and conclusions were valid and credible, then this new info is contradictary to his previous test. Where is his mistake.

[Chuck S]

Greg,

The problem is not Sanjay's data. It is your misinterpretation of such data. To clearly outline and feed correct numbers tests need to be run under the same variables. Most of the tests you see like David pointed out where mogul bulbs with no reflectors. The 250watt was tested in another way. This is in essense apples to oranges. For accurate information one needs to line up and compare apples to apples. Sanjay Joshi and Dana Riddle two men who lead the front on lighting have been testing things under same circumstance situations. These two mean deserve our respect as most of them have put alot of money out of there own pockets to provide this information. Some of this stuff was released last year at MACNA. Just because Sanjay has not released written works it does not makes it no less credible. At the time of MACNA he was not even done full analysis. I spent quite a bit of time talking with these gentlemen last year. His prior data is accurate with the variables it was tested under thats it. You put a 400watt mogul with the best reflector next to a 250watt HQI with the same reflector and I think the numbers tend to show the opposite of what you beleive. Lighting testing is ongoing. I said this before and say it again. Whatever your happy with and works for you great.

[greg c]

I don't think the misinterpretation is mine. You continue to suggest that the 250 HQI DE was tested with a reflector. That was the case with the 150 watt HQI but not the 250 watt (at least no where in the test is this suggested). Did Sanjay tell you that the 250 watt HQI was tested with a reflector? If he did, he sure misled the readers of his article that mentions nothing of the sort. Had the bulb been tested in a pendant, i see no reason why Sanjay would have removed the UV sheild. As i have stated before the 250 watt HQI bulb was not, I repeat, was not tested with a reflector. And if it was it would be a mistake IMO for Sanjay to come to the conclusion that it was the (To quote Sanjay Joshi) "obvious" choice for 250 watt bulbs.

[Chuck S]

Greg you are making assumptions on Sanjay's data. I read the articles on the 150watt bulbs. I read the data on reflector's ran with a 400watt 10K Ushio bulb.

Now the only published 250watt articles I see is this
http://www.animalnetwork.com/fish2/aqfm/1999/dec/features/2/default.asp

Quote from article by Sanjay:
<font color="red">
The double-ended HQI lamp is very different from the other lamps tested. It is double ended, while all the others have a single screw-type base. It lacks the outer ultraviolet (UV) filtering glass bulb of the other lamps. This lamp must be used in an enclosed fixture with an UV protective shield. It does have a very nice color and has the best spectral curve of any of the higher CCT lamps tested.
</font>

Now I don't have to tell you but usually in an enclosed fixture with a UV shield means it was indeed tested with a built-in reflector. I have never seen an enclosed fixture for a HQI bulb without a built in reflector. /ubbthreads/images/graemlins/wink.gif

The 400watt Ushio which has the par posted is not tested with a reflector. Now also lets take into account each bulbs best designed ballast to drive the lamp. If you take the 250watt Ushio and place it with it's best ballast and reflector and take and do the same with a 400watt 10K which runs best on a blueline ballast if memory serves me and it will not beat a 400watt mogul.

Now if you want to say a 250watt HQI beats a 250watt mogul hey I am right there with ya on that one. /ubbthreads/images/graemlins/smile.gif

[greg c]

Let me break it down for you!
"Greg you are making assumptions on Sanjay's data."
<font color="red"> </font> What assumptions have I made?

"I read the articles on the 150watt bulbs."
I am discussing the 250 watt HQI

"I read the data on reflector's ran with a 400 watt 10K Ushio bulb."
That's nice, but YOU are assuming that the 250 watt HQI bulb was using a reflector making this a equitable comparison.

"Now the only published 250watt articles I see is this
http://www.animalnetwork.com/fish2/aqfm/1999/dec/features/2/default.asp" (http://www.animalnetwork.com/fish2/aqfm/1999/dec/features/2/default.asp)
I don't have access to that site from this computer so I will let you know later if that is the one I am referencing.

"Quote from article by Sanjay:
The double-ended HQI lamp is very different from the other lamps tested. It is double ended, while all the others have a single screw-type base. It lacks the outer ultraviolet (UV) filtering glass bulb of the other lamps. This lamp must be used in an enclosed fixture with an UV protective shield. It does have a very nice color and has the best spectral curve of any of the higher CCT lamps tested."
The term (must be used with) unfortunately is making you assume that the test was performed with these items. If you know that the UV filter was not used (but must be used with) why are you assuming that the reflector was used. Maybe you don't know this, but a DE bulb's clips can be purchased separately.

"Now I don't have to tell you but usually in an enclosed fixture with a UV shield means it was indeed tested with a built-in reflector. I have never seen an enclosed fixture for a HQI bulb without a built in reflector."
Usually, does not have the same meaning as always. Once again, If you know that the UV filter was not used (but must be used with) why are you assuming that the reflector was used.

"The 400watt Ushio which has the par posted is not tested with a reflector."
True, but irrelevant unless one makes the assumption that the 250 watt HQI was tested with the reflector.

"Now also lets take into account each bulbs best designed ballast to drive the lamp. If you take the 250watt Ushio and place it with it's best ballast and reflector and take and do the same with a 400watt 10K which runs best on a blueline ballast if memory serves me and it will not beat a 400watt mogul."
This is true, the 250 watt mogul Ushio will not beat the 400 watt Ushio mogul. Sanjay never stated what brand of bulb the 250 watt HQI DE bulb was. (my guess is AB) But none the less no 250 watt bulb tested including the DE beat a Ushio on a blueline. But as for the reflector issue it is irrelevant because there was no relector used for the 250 HQI.

"Now if you want to say a 250watt HQI beats a 250watt mogul hey I am right there with ya on that one."
How can you say that, There is no difference. A HQI bulb is simply a mogul bulb without the glass envelope around it. (see you first post of the thread) A 250 HQI does not put out more PAR than a Mogul. Period. (see your 2nd post in the thread)

[Chuck S]

Yes indeed you are making assumptions. There is only one posted 250watt article. Sanjay said in the that one article posted that the HQI was tested in an enclosed fixture with UV lense WHICH MEANS in a reflector unit. I discussed this with him last year when he was doing his new tests. When he says in an enclosed fixture with uv shield it means just that. I beleive the actual unit used was a donated PFO hqi enclosure which if I am not mistaken since I also own one has a built-in reflector.

If you look at the PPFD of the 10k 250watt HQI it is 128

Looking at the highest PPFD of the 250watt 10K mogul tested it is 77.

Now if you take the mean average increase in PPFD increase that occurs with the use of a reflector then you add about 25-30% on this number. Using these findings on can correlate a mean average and see that the HQI in the same wattage range beats out all others.

[greg c]

I can only hope that Sanjay will some day test the bulbs the way we use them with their recomended reflectors an ballast. And possibly in water. I must agree to disagree for the time being until Sanjay's new data is released. Good debate Chuck &amp; Mike. /ubbthreads/images/graemlins/applause.gif

[Chuck S]

As you see there is no direct data to support your position. It is good to debate. This reminds me of the debates we use to have before alot of the people shut up after MACNA.

Alot of people claimed the 250 hqi was more powerful than a 400watt mogul but shut up over the last year quickly.

You can disagree all you want yet every lighting guru I know states a good reflector gives a light a good 25-30% increase in PPFD over no reflector. Given these factors and Sanjay's latest test the results are very accurate.

What ya doing in September?? Why not come to MACNA and talk with Sanjay directly. He is a hell of a nice guy and loves chatting shop over a free beer. /ubbthreads/images/graemlins/wink.gif Some of the best MACNA talks are in the hotel bar. Come to Louisville and I will buy ya a beer and we can sit there talking to some of the guru's in the industry.

[greg c]

Say what you want. I tried to sugar coat my last post to end this argument but you appear to have to get the last word while also throwing in a sort of cheap shot. You obviously can't even see how you continue to contradict even your own statements in the same thread. How can any one have faith in your views when you contradict them as often as you change underware. I reviewed another post a while back where another reefer had you thowing fits because of his pictures of his tank lit by a single 150 watt HQI DE. If that person was following this post he would be thinking it was Deja Vu! Heck you won't even acknowledge or admit that this happens, it's pathetic!

There is no data that supports your claims that the 250 watt HQI DE was tested in a reflector with the UV glass. Quite the contrary. If you read the whole article it clearly stated that no UV glass was used and nowhere does it state that a reflector was used. Unfortunately you continue to refer to data and facts from the 150 watt HQI test to support your argument.

I have never stated that the 250 was brighter than the 400 watt Ushio but only the Radium. Quit with the B.S. I understand why you are trying to justify your position. We all know Sanjay came out of the test with a high opinion for the 250 watt HQI DE bulbs. I talked to Sanjay, when he visited our club last year, he said the the 400 watt radium is garbage monochromatic bulb and a waste of $. I feel that the Radiums look beautiful on tanks despite Sanjay's conclusions. Maybe some day you will change your ways and appreciate other's views and opinions instead of forcing them on others and passing them off as fact.

You are and experienced reefer with a beautiful tank and you run 400 watt bulbs. I will have a beatiful tank only running it with 250's. I'll let you know when we get the results from the PAR meter then you can test your radiums and see how they compare. I will admit that your Iwasaki's will blow my 250's away. Unfortunatly for those using 400 watt bulbs, there are some bulbs on the market that can't match up to the 250 watt HQI DE. Period!

[Chuck S]

You will see what you want as well. That statement goes both ways my friend. I have nothing against HQI. I like I said use 150watt HQI on a tank. I am relating my experience and knowledge and understanding of the posted data as well as behind the scenes conversations with some people well known in the lighting industry.

I know exactly who you are talking about and he was proven wrong by many people not just me. We actually put side by side photo comparason's of 400watt versus 250watt HQI. This person has been banned by every board out there for insulting members. Many Many experienced reefers hold the same point as me. I said many many posts back each to his own. We all have the right to our opinions. There is no need for you to get insulting. I enjoy a good debate. I am just merely pointing out there is no data to support your theory. There is no need to get bent. Go enjoy your 250watt HQI bulbs and happy reefing.

[greg c]

Now that Sanjay's results have been published what do you think of the results? The 150 HQIs and the 250 HQIs were tested WITH the reflector and the UV shield. We now have direct comparison ability with the 400 watt mogul bulbs w/reflectors.

[Chuck S]

No we do not. That is what I have said all along.

The problem Greg is you miss key points my friend. A few lines down is this just like in his original article two years ago when he used a a DE with reflector when no other light was tested with one which you refused to acknowledge.

[ QUOTE ]
One critical difference between Part I and this article is the fact that in Part I, the same lamp and ballast were used with all the reflectors. This allows for a direct comparison without the influence of the ballast or lamp as a variable. Because the AB Spacelight fixture features an integrated ballast and would be used in this configuration we did not try to remove the ballast that came with it. However we did use the same lamp for the tests. The effect of the ballast hence cannot be completely isolated from the raw data, but the % dispersion plots presented help normalize the data with respect to the highest intensity thus reducing the impact of this variable. The % plot can hence also be used to extrapolate the light distribution for different ballast and lamp combinations using the same reflector. Additionally, each of these reflectors is sold with a UV shielding glass built into the fixture. Each reflector was tested with the glass shield that is sold with the reflector. The effect due to the difference in the glass shield cannot be isolated from this data, but once again is captured within the % distribution plots.

[/ QUOTE ]

There has been no direct comparison with those lighting system's together. For a direct comparison as I have said all along you need to use the same ballast same reflector and test the bulbs. Do you see any of the exact reflector's in the first test used in the second test? Of course not!! Not one is the same. The PFO reflector used in the HQI fixture is different by the PFO mogul reflector. However things look good for the DE bulbs here.

[ QUOTE ]
An interesting comparison is the one between 250W DE systems and the 400W lamps reflector systems. Since both used 10000K lamps (although from different manufactures, and of different styles), we could try to determine whether we can replace 400W systems with 250W DE lighting system. This would be economically quite beneficial to the aquarist, in terms of savings in power and minimizing heat additions to the tank. Interestingly when comparing the total incident light over the 3X3, 2X2 and 1X1 areas there is only a slight decrease in total incident light, while the lamp power is decreased by 37%. Why is there such a disproportionate difference? One possible explanation could be that the 400W fixtures are not as efficient as the 250W DE fixtures – the small size of the DE lamp allows for better reflector design and allows more of the light to get out of the reflector. With the 400W systems, the larger size of the lamp envelope may be causing some of the light to reflect back into the lamp envelope. Another possible explanation may be that the metric being used (sum of the total light at all the measured points in the specified region) is not capturing this correctly. A better metric may be the integration of the volume under the surface in the intensity distribution graphs. This aspect of the comparison needs to be analyzed further since it has significant practical implications. For now we can make this comparison by visually analyzing the graphs showing the light intensity and distribution.

[/ QUOTE ]

Maybe in part three we will get some real answers to what I have talked about. These questions were posed last year. Problem is with these test results is your getting popular light packages tested together and not direct results of different lights in different packages. I mean lets see this would be a direct comparison Greg.

example--AB 10000K 250 DE VERSUS AB 10000K 400 using the same HQI ballast and the same reflector. Now that can not be done since the reflector does not exist. Do you think maybe mogul bulb users will ever see a hammertone reflector in the same config as a DE. All ya need to do is make it big enough.