[Castle Rock Reef]

I have posted a similar question elswhere and want to see if I can get a response to these questions.

1) Why metal halide over VHO lighting? The answers I have seen so far are shimmer, to skip the upgrade, because I will want it later.

2) What specifically makes MH better than VHO?

I will be setting up a 90 gallon and am looking get about 5 watts per gallon. My understating on corals and clams is that it is placement not all power. Am I wrong?

Thanks,
Jim

[chromis]

Mainly because MH is alot more concentrated then VHO, which is spread out. MH can also penetrate the water better then VHO. Also, with MH you dont have to worry about putting clams high up in the water column, beleive me, they look like $hit when they are up high. Its best to have them lower where you can see the mantle.



HTH
Andrew

[Castle Rock Reef]

Concentration and penetration are certainly valid reasons to go with MH.

What about Dusk/Dawn affect? Is it really necessary? Can you do that with kust NOs?

Thanks,
Jim

[Ironreef]

vho will give added light with but for dusk/dawn no lights are good enough.

[flaminangel]

I thought I'd share my experience with MH

For a couple of years now I have run only VHO's and been very happy. I just couldn't see any reason to switch to MH because VHOs were working for me. A couple of months ago we set up a 30 gallon long to be nothing more than an anemone and clown tank. It was run with nothing more than 3 50/50 NO fluorescents. The bulb tip anemone has been fine (of course, I feed daily; but that's another whole topic). Less than a month ago I added a 175 watt 10,000K MH. The shimmer lines are nothing short of spectacular! And the anemone has flourished under it.

Right now, I'm sitting here looking at both tanks (of course, I have arranged my house so I have a clear view of the 75, which is lit solely by VHO, and the 30 from my computer ) and the difference is amazing. I only thought VHO looked good. MH is amazing. I'm now planning on adding MH to my 75.

I think, in the long run, you'll be happier if you go with MH from the start. I certainly wish that I had. The look is much more natural.

JMHO
Stephanie

[Starmstr]

The main reason for using MH is PAR. Which is the availability of a defined range of spectrum and intensity which allows the zooxanthella, a symbiotic algae within the corals to use the light provided.

[blue]

I guess im going to be diffrent then the rest of you. I had two 400 halides supplemented with PC on my 80 gallon tank the sure were bright but my fish were not happy and never came and neither did my shrimp. SO i switched to all Pc's and my fish colors h are better then ever and my shrimp are growing rapidly and i could less about a shimmer on the rocks. The tank also look much clearer to me so in my experince i like PC's better then halides i think will try HQI in the future as i do want to keep SPS corals on down the line. This is just my experince and my opinon.
Thanks,
Blue

PS: The dang algea on the sand still wont go away though

[thezookeeper]

I have a 75 gallon with 2-250 watt Iwasaki's and 2 40w NO actinics. I love this setup on this system. IMO, it is perfect for the inhabitants. The PAR, as mentioned before is important for the growth of corals and inhabitants. MH is a point source of light, whereas VHOand PC are not. The light is more intense with MH. And the shimmer is awesome. As far as blue is concerned, I think that the 400 watters are overkill for the height of an 80 gallon which is basically no bigger than my tank. I firmly believe that if you had gone with 250's blue, you would have loved it. But I seem to remember your parents making you get rid of them due to electricity? So now in your case, PC is the only choice you have. I just do not want someone else to take your post as the reason not to consider MH lighting. The benefits outweigh the cons. Cons are the heat issue. You must have a way to cool your tank. I use two small 4 " fans in my canopy and have no problems keeping a constant temp of 80-81 degrees. Also MH consume more electricity than VHO's. You can check my web link below to see my lighting when first set up to get an idea. Someday I will upgrade my NO actinics to VHO's. I love actinic lighting! Also, I had a 10 gallon minireef with 64 watts of PC lighting prior to my current setup. The MH blows the PC lighting out of the water. The coral growth has been amazing with the MH and slower with the PC's. HTH


Joanne

[blue]

zookeeper,
Yes electricity consumption was a problem but not one that made me get rid of the lights. I think would have been happeir with 250's instead of 400's to. I bought a pc hood and will when money permits buy a lighting set up light ninong and have two seperat hoods hanging from my ceiling. Im hoping i will like the HQI lights better.
Thanks,
Blue

[scubadude]

Originally posted by Starmstr
The main reason for using MH is PAR. Which is the availability of a defined range of spectrum and intensity which allows the zooxanthella, a symbiotic algae within the corals to use the light provided.

Bingo! just as Starm and Zoo said its the PAR! you will never come close to duplicating the par that the natural rays of the sun puts out.....but the MH's are definately much closer! There are alot of SPS at low tide that are exposed to the air and NO water....however these corals still thrive.....they love the sunshine!! there have even been reports of M. Capricornis growing above the water line on ppls aquariums.....they just keep stretching to find that PAR baby!

[PerryinCA]

Originally posted by scubadude


Bingo! just as Starm and Zoo said its the PAR! you will never come close to duplicating the par that the natural rays of the sun puts out.....but the MH's are definately much closer! There are alot of SPS at low tide that are exposed to the air and NO water....however these corals still thrive.....they love the sunshine!! there have even been reports of M. Capricornis growing above the water line on ppls aquariums.....they just keep stretching to find that PAR baby!

Couldn't be more true. Also, don't underestimate the ability to efficiently focus the light of a MH compared to the flourescent. on a watt to lumens measure, they look similiar, but the flourescent loses lots of light to ambience. Parabolics and MH are more bang for the buck in the long run.