[big 5]

opinions of hqi 250 de
growth of coral?

10,000 or 20,000k bulb?

does color of coral stay blue/ purple etc. or turn brown?

can't decide 250 hqi de or 400

[Poseidon]

I use 250 watt 10K bulbs myself. They are Mogul base but they should be very close to what a DE is anyway. My Corals stay whatever color I bouhgt them, and seem to grow really well.

[Ninong]

Originally Posted by big 5

opinions of hqi 250 de
growth of coral?

10,000 or 20,000k bulb?

does color of coral stay blue/ purple etc. or turn brown?

can't decide 250 hqi de or 400

Generally speaking, you would get more growth with a 10,000K lamp than you would with a 20,000K lamp because the 10,000K lamp would have more PAR and a better spectral distribution. IMO, true 20,000K lamps are good for adding extra blue light but should always be used in conjunction with either 10,000K or 6500K lamps so that you get complete coverage of the entire PAR range, including the important 670nm wavelength that is crucial to Chlorophyll-a. Chlorophyll-a has two action peaks, one around 440nm and the other around 670nm. I chose 250w 10,000K HQI DE lamps over 400w mogul base lamps because the 250w 10,000K HQI DE lamps had more PAR than most 400w lamps and used less electricity and produced less heat.

Right now I am running AB-10000 250w HQI DE lamps, which the manufacturer says have an actual Kelvin color of 13,000K. I also have Ushio 10,000K HQI DE lamps that I will be running once I replace my AB lamps. That's just because I happened to find them on sale a long time ago. I did try out the Ushio lamp for a few hours in one of the sockets to see if I could see any difference between it and the AB lamp but I can't say if I noticed any difference or not. Both lamps were fairly new at the time. Some people say that the AB lamp is maybe a tiny bit bluer than the Ushio lamp.

There are a couple of new brands on the market that were introduced within the past several months. Feedback from hobbyists using these new lamps is mixed. A typical comment from one hobbyist was that he liked the lamp at lot, he just wished it had lasted more than a month. I guess they sent him a replacement. The interesting thing is that some of these newer products are available in HQI DE versions as well as mogul base versions. I wouldn't mind trying one of these new 250w HQI DE lamps if (1) The PAR was comparable to what I presently use, (2) The color was a bit bluer than what I presently use, and (3) The reliability (manufacturing quality) was acceptable. Chances are that I have set up conditions that may be difficult to meet.

A couple of years back everybody was raving about the ALS 14,000K Sunburst (appropriate name) lamps based on appearance alone. Many people switched because they like the bluer appearance. Then you started to see posts about high rates of infant mortality with these lamps -- many lasted only a few weeks to a few months before exploding or failing in some other less spectacular fashion. These posts were always accompanied by reports that the vendor was very nice about replacing the defective lamp, no questions asked. But after a while you began to wonder about the quality control procedures at some of these Chinese plants. Then someone actually ran some PAR measurements and that pretty much ended the infatuation with those lamps.

Hopefully that won't be the case with some of these newer lamps on the market. Hopefully they will be a quality product with good PAR and a really nice appearance. Hopefully.

There are several threads on Reef Central started by JB_NY that include lots of pictures he took of his tank with various different brands of metal halide lamps, including two new brands, and some PAR measurements that he did himself for comparison.

[bowfront]

Originally Posted by Ninong

Right now I am running AB-10000 250w HQI DE lamps, which the manufacturer says have an actual Kelvin color of 13,000K. I also have Ushio 10,000K HQI DE lamps that I will be running once I replace my AB lamps. That's just because I happened to find them on sale a long time ago. I did try out the Ushio lamp for a few hours in one of the sockets to see if I could see any difference between it and the AB lamp but I can't say if I noticed any difference or not.

Hi Ninong, regardless of what AB may claim I think the lamps you (and I) are using are not 13k. Actually I think the 13k label is more specific to the AB SE version. I don't see anything on the AB 250w DE box that lists a Kelvin color. Sanjay's most recent article comparing 250w DE bulbs found the AB bulb to be more like 9,132 K.

That said I personally don't find the AB 10k DE's very attractive looking w/o some extra actinic (I use VHO). If you want a really blue look I would consider the new AB 20k DE bulb. These are supposed to be the brightest and best looking of the 20k 250w DE's. Otherwize you might consider a 13k or 14k bulb such as the Megachrome 13k by Geismann that seems to be getting good reviews. Hamilton also has a new 14k DE on sale for $70 that I haven't seen in person.

IME 10k DE's are not bad looking with actinic but they can be tricky in trying to maintain good blue/purple SPS color. Greens, pink, reds seem to do better under these. Personally I'm going to try another bulb next time around specifically for better coral colors.

Hard choice picking the right bulb and can also get expensive if you want to rry them all.

[Ninong]

Originally Posted by bowfront

Actually I think the 13k label is more specific to the AB SE version. I don't see anything on the AB 250w DE box that lists a Kelvin color.

AB-Aqualine/Aqua-Medic claims that ALL of their AB-10000 lamps are actually 13,000K. They have made that claim since they redesigned them in 1994. I confirmed that with them by email three years ago.

Here is their statement from their website:

The aqualine 10000 lamp has a colour temperature of 13000º Kelvin and a high percentage of the light output is at the blue end of the spectrum. aqualine 10000 was the first metal halide lamp to simulate the light conditions of a coral reef and the new lamp with its improved getter gives long term colour stability and results is an even more realistic looking aquarium. The corals show their natural colours, and the lighting encourages excellent growth. aqualine 10000 helps to transform your aquarium into a perfect reef tank.

70 Watt double ended 250 Watt single ended E 40
150 Watt double ended 400 Watt single ended E 40
250 Watt double ended 1000 Watt single ended E 40
175 Watt single ended E 39

[bowfront]

I've seen that claim on their website but I've also noticed that most vendors selling the AB 250w DE's are now calling it a 10k while they call the SE version 13k. Stickly marketing IMO. It tested recently with a lower CCT than the Ushio 10k.

[Ninong]

Originally Posted by bowfront

I've seen that claim on their website but I've also noticed that most vendors selling the AB 250w DE's are now calling it a 10k while they call the SE version 13k. Stickly marketing IMO. It tested recently with a lower CCT than the Ushio 10k.

Yes, it probably is a marketing gimmick but as far as AB is concerned there is no difference in actual color temperature between their single end and double end AB-10000 lamps. The only vendor that I know of who makes that distinction is Premium Aquatics and that was probably an oversight -- they simply forgot to stick the 13,000K in parenthesis next to the 10,000K on the DE lamps like they did on the SE lamps. Other vendors either call them 10,000K or they copy the manufacturer's explanation that their AB-10000 lamps have an actual color temperature of 13,000K.

I have no experience with their SE lamps but I find that their DE lamps give a crisp white appearance with no hint of yellow. However, I believe their appearance is improved with actinic supplementation and/or some 20,000K supplementation. They even offer a version of the 120cm Aquaspacelight equipped with two AB-10000 250w HQI DE lamps and a 150w Blue (20,000K) HQI DE lamp in the middle. I know someone who has that fixture and he likes it a lot.

[bowfront]

They even offer a version of the 120cm Aquaspacelight equipped with two AB-10000 250w HQI DE lamps and a 150w Blue (20,000K) HQI DE lamp in the middle. I know someone who has that fixture and he likes it a lot.

I'll bet that's a nice setup. I have used the 150w BLV Colorlite and it's a nice color blue but dim. It would make a nice compliment to 250w 10k bulbs. To get back to AB the whole color thing is a little strange IMO. They market a bulb called the AB 10000, then claim it has a 13k color, but it tests out with the lowest CCT of these 4 bulbs recently tested by Sanjay Joshi.... go figure. Actually all 4 bulbs tested had very similar spectral qualities.

From Sanjay's arcticle:

[Ninong]

The 150w Blue HQI DE lamp that is employed in the 120cm Aquaspacelight is the BLV Colorlite. That particular version of the Aquaspacelight fixture seems to be a made-in-America variant. I don't think it is available in Germany. I know from talking to Aqua-Medic about it that they chose the 150w size because of the availability of a small electronic ballast that would fit in the available space in the center of their fixture in place of the two 24w Osram blue PCs.

Another interesting article from Sanjay. I had not read that one before. Interesting that he should test the Ushio 250w 10,000K HQI DE lamp AND the HIT (BLV) 10,000K HQI DE lamp and come up with slightly different numbers since, according to Ushio's website, there is NO difference between the two lamps. They are supposed to be identical. They are listed on the same line in the catalogue with the Ushio product code (UHI-250AQ) and the BLV product code (BLV 222403) on the same line. And, of course, they are manufactured in the same Ushio owned BLV plant just outside of Munich. As far as I know they are the same lamp marketed under different brands. The differences could be the result of manufacturing variations within individual products. According to personal communication with Sanjay Joshi a couple of years ago, he told me there is up to a 20% variation in individual lamps. That would amount to +/- 10% from the expected performance.

All of his tests are very informative. In order for the numbers to be more reliable he would need at least 10 samples of each lamp and each ballast, which would mean a whole lot of money and time. I know that in some of his earlier tests he actually discarded sub-par lamps and/or ballasts and requested replacements so that his measurements would be more accurate, but in most instances he has just one of each component to work with. Still, he is doing a wonderful service for the hobby in providing unbiased results that we can refer to so that we are not left with just the marketing hype put out by the manufacturers.

P.S. -- According to AB-Aqualine, they retained the brand name AB-10000 for that lamp even after it was redesigned in 1994 because it was an established brand name. They told me it was the "model name," not the actual Kelvin color temperature, which they insist is 13,000K. I noticed on their most recent update of their website that they now refer to it as the Aqualine 10000 instead of the AB-10000 but they still stick to their claim of 13,000K for all of their Aqualine 10000 lamps. I don't suppose that's any worse than Iwasaki insisting that their new 150w medium base lamp is a true 50,000K even though it is not nearly as blue as most 14,000K or 20,000K lamps.

[bowfront]

There is indeed variance between individual bulbs and his test uses only one of each so there are still some question marks. BTW, the Giesemann bulb tested for this article was not the new Megachrome Marine that is supposed to be a true 13k when run with a megnetic ballast. It was an earlier prototype of that bulb that was actually a 10k. Althought the AB bulb tested with the lowest CCT it also tested with the highest PAR of the four.