Metal Halides for a 220g tank

[Unarce]

Hi Kim,

You could be right, as the effectiveness of the reflector plays a mjor role. It may also depend on the manufacturer. I use XM brand bulbs and made the assumption off of their spec sheet. For example, the points of Relative Intensity are roughly equivalent between the 400W SE 10K and the 250W DE 10K.

http://www.xmlighting.com/specifications.html

I'm more of a stickler for spectrum rather than intensity because I am a 20K FREAK!

 

[kim]

Useful link...many thanks ! It's always nice to see a company which is willing to publish data like that. So many don't.....

Anyway, I hope I'm right....or at least not too far wrong. Having 3 x 400 W SE's above my tank would otherwise be an expensive mistake.

8O

kim

 

[Unarce]

You're welcome.

There are always pros and cons. DE bulbs give off harmful UV-A and UV-B because of the high intensity and lack of the glass envelope that SE bulbs have. That's why they need a glass shield.

 

[Anonymous]

This is obviously a matter of preference, but I have a 78" x 32" reef tank that is 37" tall (about 360 net gallons). I am running 4x 400watt Iwasakis on a PFO EYE ballast with supplemental actinic lighting. The actinic lighting was originally 4x 96watt PC's on an Icecap ballast, but was latter switched to 3x 6' VHO bulbs (on the same ballast).

There is no way that I would say that the 400watt Iwasaki's are not enough light for my tank. In fact, I have had some difficulty in aclimating sps corals to the high light levels. To compensate, I usually stagger the MH's so that all 4 are only on at the same time for 2 hours in the middle of the cycle.

I am happy, but not thrilled, with the lighting. If I had to do it all over, I would probably have gone with either 4x 400watt 10000K bulbs (plus supplemental actinics), or maybe 5x 400watt 13000-14000K bulbs (and no supplemental actinics). Either est-up would have given me less lumens, but better coral coloration.

Just my 2 cents.

 

[Unarce]

This is obviously a matter of preference, but I have a 78" x 32" reef tank that is 37" tall (about 360 net gallons). I am running 4x 400watt Iwasakis on a PFO EYE ballast with supplemental actinic lighting. The actinic lighting was originally 4x 96watt PC's on an Icecap ballast, but was latter switched to 3x 6' VHO bulbs (on the same ballast).

There is no way that I would say that the 400watt Iwasaki's are not enough light for my tank. In fact, I have had some difficulty in aclimating sps corals to the high light levels. To compensate, I usually stagger the MH's so that all 4 are only on at the same time for 2 hours in the middle of the cycle.

I am happy, but not thrilled, with the lighting. If I had to do it all over, I would probably have gone with either 4x 400watt 10000K bulbs (plus supplemental actinics), or maybe 5x 400watt 13000-14000K bulbs (and no supplemental actinics). Either est-up would have given me less lumens, but better coral coloration.

Just my 2 cents.

You can't argue with preference if someone prefers the look of yellow, but they can't claim that it's best for corals without any proof. The way it appears is it just doesn't make sense to raise SPS under Iwasaki's. Studies show that the 2 primary reasons for mass bleaching in our oceans are extreme temperatures and intense light. At high noon on a clear day, photosynthesis is nearly inactive in corals. As I mentioned before on this thread, the exuberant amount of 540-640nm in Iwasaki's are almost a waste and have no benefit to corals. This might explain your difficulty when acclimating. Next time you change your bulbs, just go with 4 20K's and you'll be thanking me later. :wink:

 

[Unarce]

Oops! Sorry for the double-post.

 

[Anonymous]

This is obviously a matter of preference, but I have a 78" x 32" reef tank that is 37" tall (about 360 net gallons). I am running 4x 400watt Iwasakis on a PFO EYE ballast with supplemental actinic lighting. The actinic lighting was originally 4x 96watt PC's on an Icecap ballast, but was latter switched to 3x 6' VHO bulbs (on the same ballast).

There is no way that I would say that the 400watt Iwasaki's are not enough light for my tank. In fact, I have had some difficulty in aclimating sps corals to the high light levels. To compensate, I usually stagger the MH's so that all 4 are only on at the same time for 2 hours in the middle of the cycle.

I am happy, but not thrilled, with the lighting. If I had to do it all over, I would probably have gone with either 4x 400watt 10000K bulbs (plus supplemental actinics), or maybe 5x 400watt 13000-14000K bulbs (and no supplemental actinics). Either est-up would have given me less lumens, but better coral coloration.

Just my 2 cents.

You can't argue with preference if someone prefers the look of yellow, but they can't claim that it's best for corals without any proof. The way it appears is it just doesn't make sense to raise SPS under Iwasaki's. Studies show that the 2 primary reasons for mass bleaching in our oceans are extreme temperatures and intense light. At high noon on a clear day, photosynthesis is nearly inactive in corals. As I mentioned before on this thread, the exuberant amount of 540-640nm in Iwasaki's are almost a waste and have no benefit to corals. This might explain your difficulty when acclimating. Next time you change your bulbs, just go with 4 20K's and you'll be thanking me later. :wink:

Well, this is not my first reef tank, but it is my deepest. My previous reef tank was a 24" tall 200 lit by 3x 250watt Iwasaki's and 2x 6' VHO actinics. I had sps colonies growing out the top of the tank and more than 18" across.

When I was planning the lighting for this tank, most everybody that I talked to and here on this board were adament that 400watt Iwasaki's were the only real choice for an sps tank. Like you, I have re-thought this and have considered changing. (Although the prevailing opinion of those that I talk with are still convinced that I could not have a better set-up.) But I have one problem - I am using the PFO EYE ballasts, which only run the Iwasaki's. Switching out the guts of the ballasts will cost me $240 ($60 each).

Although I may still do this at some point down the road, my tank is still very young (less than 2 years old), and I am finally starting to see some progress with a few sps colonies that I thought had been previously wiped out by an algae problem that I had last year. In the meantime, I am trying to experiment by obtaining sps frags from different sources to see which are more adaptable to my set-up.

Minor question? Why the reccomendation for 20K's vs. 10K's or the newer 13.5/14K's? It seems to me that the 10K Ushios would provide some benefits over the 20K's.

 

[Unarce]

Minor question? Why the reccomendation for 20K's vs. 10K's or the newer 13.5/14K's? It seems to me that the 10K Ushios would provide some benefits over the 20K's.

I really didn't like the look and extra heat from my 10K Ushio. I used a 20K for about a month, and the colors my SPS developed were amazing. The polyp extension was greater as well. Growth might have been the same if not better under the 20K. Needless to say, I sold the 10K Ushio on this website. My A. Tortuosa really took off after the change.

 

[Anonymous]

Are you supplementing the 20K's with actinics? I would assume no. Are these 400watt, double-ended bulbs? Even so, I would still be concerned that I will lose to many lumens by replacing 400watt Iwasaki's with 400watt 20K's. But I will have to look into this issue some more.

 

[Unarce]

I'm using 250W double-end as stand-alone, although I know of a few that use 20K's with actinic supplementation. I think the number of lumens is a bit overrated. You'll get tons of lumens out of a 4300K bulb, but the corals might die in a week or two. It's better to give them more of what corals use, and less of what they don't which is all those extra lumens of green, yellow, and orange spectrum.

 

[Anonymous]

I understand what you are saying. However, it is my understanding that there is still plenty of debate with respect to your assertion that the additional lumens in the yellow, green and orange spectrum that are provided by 6500K Iwasaki's are not utilized by corals.

 

[Unarce]

I completely understand that and wouldn't doubt it. A majority of the trends that we see are born from hobbyist speculation or assumptions. If you were to ask for any evidence that the green, yellow, and orange spectrum had any significant use in corals, you're not going to get any response.

There are some inshore species of SPS that have certain pigmentation that protects them enough and allows them to survive in intense light and high temperature conditions.

 

[kim]

You can't argue with preference if someone prefers the look of yellow, but they can't claim that it's best for corals without any proof. The way it appears is it just doesn't make sense to raise SPS under Iwasaki's. Studies show that the 2 primary reasons for mass bleaching in our oceans are extreme temperatures and intense light

Hi again.

The heat bit I understand. I don't know about the light. Sun is getting dimmer (don't worry, still time...), the atmosphere more polluted with crap.....have light levels in the ocean risen damagingly above the levels where corals evolved ? With the ozone problems I suspect that more UV is getting thru' - but that is an argument against blue light, not Iwasaki yellow.

And Iwasaki's do mimic (not perfectly) conditions at the ocean's surface.

Evidence does suggest that corals shut down for lunch ! Too much light ? Or maybe just digesting the morning's supply of sugars. Hic !

As far as I can see, there is strong data that suggests that SPS quickly become saturated with light energy at reef intensities, and anecdotal evidence suggests that "bluer" light (eg getting toward UV) will tend to cause the colouration most of us seek. But then again, do the Iwasaki's do harm ?

To a large extent I suspect that "blue" lights are created not so much by adding blue as by excluding yellow etc. so are Iwasaki's so deficient ?

And then does red/yellow cause damage ? Infra red = heating, but I am talking visible red, which does not.

I'm new to the "spectrum" discussion, so do look forward to opinions.

:?:

kim

 

[Unarce]

I wouldn't go as far to say that 6500K would be damaging. Corals can adapt to them, but I feel that a bluer spectrum would make a healthier environment. Red does play an important role for photosynthesis.

Although Iwasaki's do mimic light at the ocean's surface, the shorter wavelengths become the dominant spectrum after just one meter below the surface. That is what most corals are accustomed to in the wild.

Here are some links that I've shared on previous threads:

http://www.reefs.org/library/talklog/s_ ... /acpPC.jpg
http://www.reefs.org/library/talklog/s_ ... 02/pas.jpg
http://www.science.uts.edu.au/des/Staff ... hesis.html

Iwasaki's give out great portions of blue, but perhaps all that unnecessary green, yellow, and orange light holds corals back from their true potential.

 

[Unarce]

Like a sculptor, who chisels away what is not needed to reveal the truth.

 

[kim]

Many thanks.....I'll slide down those links later when I have a mo'.

kim

 

[bleedingthought]

Too late!!
Will have to stick with my 400w moguls and the 4x96's

remember i got 2 10k 400w and 1 20k for the middle

Your tank is the same size as mine (220g vs 210). Do you have an equipment/etc list describing anything in your tank somewhere?

WOuld be interested to learn more about what you have going on.

Mine:
220g
born on 11/30/03
200lbs live rock, 200lbs live sand
hsa-250 skimmer
you know the new lights
looking for a calc reactor now
3 clowns, 1 naso tang, 1 cleaner shrimp, 4 damsels, 1 gobie
1 leather, 1 christmas tree worm
10 blue leg hermits, 6 nassisurius snails

Eric, did any of these survive?

On a happier note, it seems like you have a really cool setup going here. Do post pictures (even if right now it's just a FOWLR) when you get the chance!!!

 

[bleedingthought]

Man, reading over this thing makes me realize how much things changed in the past 2.5 years!!!