175Watt vs. 250Watt/Reef Lighting 10/25/09
<Good morning, Jeff>
I really appreciate all the great advice you provide. It has been very helpful.
<You're welcome.>
I now need some help on which metal halide would be the best for my new 120 gallon (48x24x24) reef tank. My plan is to use (2) XM 250W 10K SE or (2) XM 175W 10K SE metal halide bulbs within (2) LumenMax Elite reflectors.
I also plan to use a Galaxy Electronic Ballast.
Sanjay Joshi tested both bulbs with the Galaxy ballast with the following results: the 250 watt had a PPFD of 133.2 and a CCT of 9860, the 175 watt tested at 80.4 for the PPFD and 10514 for the CCT. The PPFD for both bulbs will no doubt be higher within the LumenMax Elite reflectors.
<Should be, and for other readers sake, the acronym PPFD (PAR/PUR) means photosynthetically available/useable radiation, or the intensity of the bulb between 400nm and 700nm, which is what our corals use. The CCT is the actual corrected color temperature.>
The corals I plan to keep are SPSs, such as Montiporas and Acroporas. I also plan to keep LPSs such as Euphyllia divisa, E. ancora, E. glabrescens and my personal favorite Plerogyra sinuosa. I may also keep a xenia, some Zoanthids and perhaps a gorgonian.
My concern is if I go with the 250 watt bulb would it be too much light for the LPSs?
<No, not at 4 watts per gallon and a 24" deep tank.>
Would the 175 watt bulb be enough light for the SPSs?
<Should be enough with a 48" long tank using 10K lamps. I run two Ice Cap 175 watt 10K's in a 60" long, 18" deep tank and is providing good SPS growth.>
I have always thought I would go with the 250 watt but the more I read about the LumenMax Elites the more I am worried that it may give too much light for the LPSs. If this too much light would the 175 watt bulbs be enough? What is your opinion?
<I'd go with the 10K 175's if it were mine. If you decided to run 14K lamps or higher, go with the 250's.>
If I may, an off the topic question, what are the two best "reef safe" centroyge <Centropyge> angelfishes?
<In my experience, I've always had the best luck with the Coral Beauty, and/or False Lemon Peel. Both have been well behaved in my system going on three years now.
Is no guarantee, with caution is always advised with Centropyge.>
Thanks again for the help.
<You're welcome. James (Salty Dog)>
Jeff

Question About MH Lighting (Effective Light Spread?) – 07/17/09
Hello,
<<Howdy>>
How are you?
<<Fine thanks>>
I have a coral tank, but for it now I use a 72" Aqualight Pro fixture 3 x 150 watt 10000k MH lamps and 4x 96 watt true Actinic on a 125 gallons tank (72"x18"x22"),
<<Sounds fine to me>>
but I am planning of building another coral tank dimension (72"x48"x 10").
<<That last is an interesting dimension>>
I was wondering if I would be able to use the same light?
<<Sure… The fixture can be raised to adjust intensity for the shallowness of the tank…though you will likely need two fixtures, one behind the other, to cover the 48” depth>>
I know that the tank being 48" wide can cause the side to have less light but if I raise the lamp a little bit higher (since my tank would be less deep) would I be able to at least get light for around 36 inch wide or a little more and still getting good light for the corals even on the side?
<<That will depend on several factors such as the quality and style/shape of the reflector in the fixture, the height it has to be raised off the water to get the “spread” you want, and the type of corals; or rather the light-requirements of the corals, kept along the perimeter of the lighting field>>
I am more a fish guy than corals but I am learning all the time ;)!
<<Is a continuous process indeed>>
By the way the reason I am doing this is because I have a store and I am changing the setup.
<<Okay>>
And like everybody else do not want to spend extra money!
<<A popular notion…especially these days>>
Thank you,
Leo
<<Happy to share… EricR>>

Work Lighting Fixture Good For The Reef Tank? – 07/14/09
Hello,
<<Greetings>>
So we had to change our 250 watt metal halide ceiling lights out at work and I was able to bring the fixtures home.
<<Lucky you!>>
Would I be able to use these on my reef tank or are the ballasts different?
<<It’s likely these ballasts will work fine with a hobby-spectrum MH bulb (though maybe not at peak/optimum performance). But, this is easy enough to test if you have/can borrow a bulb. Also… If you know or can determine the ballast type/model, you can do a web-search and find which “aquarium” bulb types and/or manufacturers are thought to work best with the differing ballasts>>
Will 250 watt aquarium lights fit in these kinds of sockets?
<<If these are screw-type sockets they are probably mogul-base sockets for this wattage, so yes, they should fit. My first MH setup consisted of DIY reflectors with “commercial/industrial” sockets and tar ballasts (very heavy…very hot running)>>
Thanks so much for your help!!!
<<Happy to share… EricR>>

Aqualight Pro Upgrade 5/12/09
I had a quick question about a light upgrade. I have a 55 gallon reef tank with softies, some LPS, and some hardy Montipora corals. My current lighting is a Coralife (4x65) pc fixture.
I came across a used Aqualight Pro (2 x 150 MH), (2 x 96 watt PC) and 3 LED's for only 200$ when they normally go for 6-800$. Few questions.
1.I was wondering what you thought of the unit?
<It is a fine unit, especially for this price.>
2.Also, having never had MH lights, what brand light bulbs would recommend as replacements. Also, what brand CP lights?
<Just about any will do, see Sanjay Joshi's site to help you select the bulb that fits you: http://www.manhattanreefs.com/lighting>
3.Because I'm switching from 11 hours of PC lighting to MH's. What would the lighting schedule be to acclimate the tank from PC's to MH's? I don't want to burn anything out.
<Well, I would start with the MH higher up if at all possible. If not, something like 7 hours a day, increasing an hour every 3 days or so will do.>
Thanks a lot for the help.
Bob
<Welcome, Scott V.> 

DIY Metal Halide Question   5/2/09 I have a small online store selling corals and frags and I was thinking of doing some coral farming. I have some 400 watt high bay industrial light fixtures my question is will these work with aquarium bulbs the ballast specs lead me to believe so my only concern is the vertical position of the bulbs. <Mmm... please send along the particular specifications for both the lamps and fixtures... Not likely these will be of use to you here. Bob Fenner> Re: James, pls have a look... more up your area of expertise than mine (thank goodness!). BobF Will do Bob. James Re DIY Metal Halide Question 5/3/09 Here is a pic of the ballast label. I would like to use the XM 15k 400watt mogul base lamps there specs say universal position and works with m59 electronic or magnetic ballast. <Hello Guy. Mr. Fenner has asked me to reply to your query. The XM, 15K, 400 watt lamp requires a M59 probe start ballast so you should have no problem using your ballast with this lamp. Be aware that the M135 and M155 are also 400 watt ballasts but use a pulse start, and would not be suitable for use with the XM lamp. James (Salty Dog)>

Metal Halide Query Not Posted In Today's Dailies   3/31/2009
Hi Bob,
Hope you left a few bottles of beer in Coz for others to enjoy.
Yesterday, I answered a query concerning problems with lamp replacement and a ballast problem and see it was not posted today. I answered and deleted as normal.
Mmmm.
James
<QUICK, like a lagomorph, check the DELETED files on the mail site for WWM... I did not see this in the SENT folder... may well be in the deleted.
If so... send back to the SENT. B>

Lost Metal Halide Query   3/31/2009
Bob,
<Big J>
Now you want me to assimilate the speed of a rat at my age. Nothing doing.
I just saw that I received a response from the gent I got the query from.
Will answer sometime today and delete which should allow you to post both.
Unless I'm in a time warp,
<I assure you we are>
I just do not recall seeing the query. It's in my inbox if you care to take a look. You are a few years younger than me and might remember more.
Regards,
James
<Doubtful. Be chatting, B>

Metal Halide questions--help asap 3/30/09 <James, this was posted ayer. RMF>
Please help ASAP!
I am still new to reefkeeping and am having a problem. First of all, I heard that MH lighting was the best. I have a 55 gallon tank, so I found a used MH fixture online used at a very decent price. The fixture isn't labeled anywhere so I am not 100% sure of the brand.
The fixture is 48" long, and contains 2 250W MH double ended bulbs. The outer edges are actinic bulbs, and down the center led moonlights are. My tank has been running wonderfully for around 8 months and mixed soft and hard corals, along with fish have thrived. Is it too much light though for the tank?
<I little overkill for a 55, but for keeping light loving corals/clams, should not be a problem as long as your tank temperature isn't going through the roof.>
The bulbs are labeled 20K blue 250W. I was told the fixture was a Corallife brand.
Now for the problem. A few days ago 1 of the lights went out. So I attempted to narrow down the cause to ballast or bulb. I unplugged the working light and hooked up the ballast to the none working light.
Nothing. So narrowing it down I have isolated the problem to be bad bulb on one side.
<OK>
To confirm this I attempted as many combinations of hookups. No matter which ballast was hooked up. Only the same light would work. So I order a bulb online. I order a CoralVue 14k 250W double ended bulb, disassemble and install the bulb. Still nothing. So I pull out the bulb that was working before, put in the brand new bulb, and again nothing. I swapped and tried every combination I could.
Results--1 bulb working in both fixtures with both ballasts. Bulb would light up almost immediately.
New bulb, & other bulb--would not work in either fixture.
<Well, one bulb was gone to start with and I'm guessing your problem may lie with the new CoralVue lamp being a probe start type lamp, and your ballast is a pulse start.
Most 250 watt DE lamps are pulse start. Pulse start lamps do not have a starting probe electrode as in the CoralVue, but start by way of a high voltage pulse, typically 3 to 5 kilovolts.>
I've got records on most bulbs that indicate the start method and type of ballast required, but CoralVue is just listed as a ? but it is a probe start lamp. Problem here is most folks think any HQI lamp will work with their ballast and that is not the case.>
So I thought I would just leave 1 working for now, and I put it back together, set it atop the tank. Roughly 3 minutes later the working bulb explodes.
<Didn't like that.>
Now all I have is my actinics running, with a lot of livestock in the tank.
How long until I get this fixed before I have major die off?
<To be safe, I'd say a week for light loving SPS/LPS. Could be longer, but I wouldn't want to chance the Zooanthellae dying off which is called bleaching. I am assuming you have corals and as the fish without light, it isn't going to be a problem.>
What do I do? Is it possible the ballasts are too weak to light the bulbs?
The ballasts do not have labels, they are encased in metal with a switch, and removable power cable.
<Is there a manufacturer listed on the old lamp itself? If so, replacing with that brand/type would ensure you would have had the right lamp for the ballast you have. There are no numbers stamped on the ballast itself, like an "M" and a number? Best to take the fixture to a local electrical shop and see if they can test the ballasts for you before investing in more lamps.>
Help Help help! I can give more details.
Thanks for your time.
<You're welcome you poor dude. James (Salty Dog)>
Luke 

Re Metal Halide questions--help asap 4/1/09
Please help ASAP!
Thanks for the response.
<You're welcome.>
More research done yesterday. Found out my fixture is an Odessa 48".
From the forum discussions this a terrible and cheap fixture.
The recommendation is that the stock ballasts with the unit only have enough power to push maybe 160W. Everything I have read recommends updating the ballasts.
So yesterday I ordered 2 Icecap 250W ballasts. Another $260 investment. I really really really hope this works, and the Icecap will power the new 14K CoralVue bulb.
<Ice Cap does state this ballast will power any 250 watt MH lamp, so you should be good to go.>
I plan--if it works, to light up 1/2 the tank with the new bulb, more the light loving coral there. Then order another bulb for the other side of the fixture.
Do you recommend using the same type and k-value bulbs for the whole tank?
Or for example can I have a 14K on one side and a 10K on the other side?
<No problem doing this, but I think you will not like the look.>
I have been forced to learn a lot quickly and your advice is greatly appreciated.
<You are welcome my friend.>
With my case of too big light for shallow tank, what K bulb and brand would you recommend? Should I move soft coral to one side and hard to another?
<No, I'd just go with two 14K lamps. I use Corallife lamps myself but I'm not saying they are the best out there, I just happen to like their 14K look. All 14K or other temperature lamps for that matter will not necessarily look the same as far as color appearance goes, some may be slightly lighter and some slightly darker in the blue range.>
Livestock consists of:
Spaghetti leather?
2 toadstool leathers?
many types mushrooms
many types of polyps
Zoanthids
Hammer Coral
Brain Coral
red Montipora
yellow Montipora
chili coral?
xenia
hard/stony coral--not sure which kinds.
fish
1 Clarkii clown
2- percula clowns
1- chromis
4- blue damsels
1-cleaner shrimp
2- peppermint shrimp
hermit crabs
snails
2- brittle starfish
Your help is greatly appreciated.
<Again, you're welcome. James (Salty Dog)>

Halide aesthetics 3/28/09
Hello fellow reefer's.
<Jason>
I have a 125 long with a 6 ft hanging halide fixture that is almost a year old now. I bought this off of Ebay and it does not even have a brand name.
I have attempted the cheap route with good success so far.
<As long as the fixture serves... the lighting components are sound, not easily water damaged, produce light of the desired quality....>
It has 3 150watt halides (HQI) and 2 54 watt T5's. My question is, this is the style where each halide bulb is in its own little compartment and so between the bulbs is just the flat fixture itself. No open reflector canopy type thing for all of the light to bounce off of. Is this a less favorable setup?
<Mmm, maybe could be improved with your adding reflectors... these are sold separately by a few companies. Do check out Hello Lights (.com) et al.>
I have seen the nice Hamilton mogul types that have the big overhanging canopies on each side of the fixture and the bulbs are more out in the open. With that style, I would imagine there is much more light reflecting off of the fixture itself giving better light production. In deciding one halide system from another, this is one topic I haven't seen a lot of discussion about. I should say however, that I really can't complain with the look of my setup as I am quite pleased. So why am I even writing in? Just for some feedback I guess.
<Fine>
Also related to this issue, the height of the fixture off of the water is another question. I have had it at about 8" all this time I would say. That's been fine but I have seen other reports in books and what not of some keeping theirs lower to maybe 4". I lowered mine to 6" yesterday.
<Mmm, there are a few considerations to ponder here... certainly heat transfer, dispersion of light, and the propensity for damage (even explosion) of lamps as a consequence of water-splashing need to be taken into account>
I haven't noticed any increase in water temp, but I notice the light in the room is a little dimmer as now the light is closer to the water. The higher the light is off the water, the more blinding light it creates for us people in the room, even with a 2" reflector hanging from the fixture
<Oh! I would definitely fashion/install a "blind" if not a fitting canopy to discount such glaring from the fixture>
I was wondering if there is a cheap way of creating some thing or way to put the lights back up a couple inches but keep the light in the tank and out of my eyes. Like propping up a strip of tinted acrylic and standing it up on the front edge of my aquarium and resting it on the fixture.
<Oh yes... there are many such possibilities... again, do keep in mind the issue of waste heat (and its removal) as well as the potential for fire>
Something short of constructing a canopy that would involve a lot of monkey business. It seems like with the lights lowered a bit more like it is now, the light is more focused directly in the tank and not so much the room.
<Do see the Net... the "prismatic" reflectors that will focus reflected light downward... that can be retrofitted>
Before with all the excess light it made in the room, it kind of took away from the dramatic effect of the light inside the tank because we as the viewers were already in a brightly lit room to begin with. By the way I don't see any negative impact on the corals at my 6" height, in fact my green open brain coral is about as big as I've seen it. About 6" across with about a 3 1/2"height. I have several LPS and a couple softies all doing well.
<Ah good. There are many "general notions" re aquariums, lighting in this case that are erroneous to poorly understood... One is how variable and vacillating actual insolation is in the wild... As your observations reveal, cnidarians don't need too-regular direct intense light to prosper. Bob Fenner>
I would appreciate any comments you might have on any of this.
Thanks,
Jason

MH Retrofit 3/20/09
Hello,
<Hi there Kiet.>
I am interested in purchasing a MH retrofit for my 125 gallon. I saw a pretty good deal online for one made by a company called Captive Sun. I was wondering if you have heard of this company or any experience with their products.
<I have, fine stuff.>
Their 72 in retrofits includes 3 metal halide moguls and a setup for 160 watt VHO bulbs rather than the standard 96 watt PCs.
<I personally prefer VHO actinics over PCs.>
Also, with my tank (6 ft long), I should go with the 3 moguls and opposed to the 2 right?
<Would be better, yes.>
Thank you,
Kiet
<Welcome, Scott V.>

Metal Halide Downgrade, e' use, matching lamp/ballasts  3/20/09
Hi,
<Hi Josh>
first I just want to say thanks for all of your guys <and gals> help.
<You're welcome.>
I have a 150g reef tank and just recently bought a Aqua Medic 72" 5x250w metal halide (all 10k). With that and the 1/3 chiller, my electric bill shot up $120 a month
<Yowsie!>
so I'm trying to be more conservative. I'm in Florida and its only March so I need a quick solution. Can I use 150w bulbs in my current hood? And will the ballast supply only 150w if that's all that's needed?
<Ballasts are matched to the lamps, that is, if a lamp has an ANSI designation of M-57, then a M-57 type ballast must be used.
Switching to a lower wattage lamp would likely work in some cases, but would overdrive the lamp. This will lead to premature failure and shorter lamp life, and likely cause an explosive failure due to rupturing of the
lamps inner and outer arc tube. My advice, don't try it. Is it possible to run the unit on three lamps providing they are spaced out properly.
Ideally, one at one foot from each tank end and one in the middle. Three 250's should provide plenty of light for your corals/clams, as I'm guessing your tank is 20" deep and 24" wide. The other option is, do your cooking on the light hood and keep the stove off.
Thank you
<James (Salty Dog)>
Josh

MH plug confusion   3/10/09
Hello Crew,
<Hello Sheldon.>
Your website has been extremely helpful to me over the past few years. You all, have help advanced my husbandry techniques exponentially; my oceanic friends thank you!
<Ah, well, thank you!>
I have never submitted a question because I could always find answers to problems from others who have written in.
<Tis our goal to have such a resource, though questions are definitely welcome!>
I am upgrading my system from a 55 gallon to a 125 gallon tank.
<Nice upgrade.>
I have my own lighting system that includes two 250W 15K MH with four 65W PC that are integrated into one system that sits on top of the tank - no canopy. The 125 gallon tank that I am purchasing has a canopy. It is from a Craigslist seller. I met with the seller to view the condition of everything before I agreed to the purchase - naturally. I noticed that the canopy had MH lights and PC fittings. The canopy had four built in fans as well.
<Good.>
I asked the seller if the MH lights had ballasts that came with it - she had no clue. She made a phone call to her mother-in-law, the previous owner, and she said the MH lights had no ballasts. She claimed that they were plugged directly into the wall.
<Hmmm.>
The wiring of the tank looked old and as if someone had wired it themselves.
Examining the plug I noticed that it wasn't a standard looking wall socket plug. The plug that was to go into the wall looked like a regular American 3 prong plug, two vertical lines and a hole for a ground, except it had two horizontal lines and hole for a ground. I had never seen this type of plug configuration before. When I returned home, I looked up the different prong type configurations from around the World to try and match them. The configuration that most closely matches is a "Type G", except the ground isn't a rectangular blade for mine, its a hole (circle). Can MH and PC lights be plugged directly into sockets like this without ballasts?
<No.>
The wiring goes from the wall directly into the mogul socket with wires that are split, which I am assuming are for the fans and the PC.
<The wiring running directly to the MH bulb splits to the PC and fan? I have to tell you my friend, this configuration never worked and is flat out a fire hazard.>
I'm thinking about taking the old lighting hardware out and taking apart my MH/PC housing and replacing the old lighting hardware with the ones from the complete fixture. If you have any insight to this problem it would be extremely appreciated!
<Your plan to cannibalize your existing fixture is far more sound.
Otherwise I would have a qualified electrician take a look at the whole thing. Better a few dollars here than no house!>
Thank you in advance,
Sheldon Young
<Welcome. By the way, the plug you describe does sound like the typical type that runs from a bulb to a MH ballast, not into the wall. Scott V.

Re: Lighting Question, MH fixt., lamps    2/13/09
Ok, I am at it again with the questions. I think I want two MH pendants to hang over my tank. My tank is at about 78 deg consistently summer and winter with not much fluctuation at all. Here is a website I have found.
http://www.fishneedit.com/metal-halide.html . They have 70 watt MH pendants for $110 and 150 watt MH pendants for $130. I have done some searching for reviews on these and have read more good than bad about them.
<I tried doing a bit of research on FishNeedIt products and did not come up with much useful information. Most buyers of FishNeedIt products use their T5 fixtures and seem to be relatively happy with them. However, I am
skeptical of their MH reflector design and bulb selection as these are the two most important factors in a lighting set up.>
If you feel these are ok to pull the trigger on, which wattage would be the best for my tank? I would like to keep mostly soft and LPS corals and maybe some SPS corals but no clams or anything like that. Do you think 2 150 watt or 2 70 watt would be best?
<Since there is not much technical detail available for FishNeedIt's MH set ups, I would suggest for you to contact the manufacturer for more information (ballast, reflector and bulb specs) and recommendation.
However, from my experience, 70W MH is relatively weak especially for taller tanks and the bulb selection is quite small compared to the 150W counterpart.>
Also, they let you pick your bulb color. I was thinking for MH that 14000K would be pretty good. Any suggestions on this would be great.
<14k should be a good common ground between the white and sometimes yellow look of a 10k and over saturated blue look of a 20k. However, keep in mind that the "Kelvin" scale is not uniform between all these bulb manufacturers and are often times arbitrary. Some 14k bulbs are whiter and some are bluer than others. It is best to ask for a white balanced picture of the bulb in operation from the manufacturer.
I know that reef lighting can be a confusing subject particularly when there's a lot of misinformation floating around. That's why I always refer reefers to the work of Sanjay Joshi
(http://www.manhattanreefs.com/lighting). If you spend some time getting familiar with his site and read his articles, you will find your decision making process a lot clearer.>
Thanks again
Matt
<You're welcome. Cheers, Minh Huynh.>

Metal Halide & T5's
Reef Lighting/Selection 1/29/09
Hey guys,
<Hiya Wayne>
I'm looking at upgrading my lighting to Metal Halides with two 24W T5 Actinics. Having a corner tank this posses at lot of obstacles as you know.
My tank is 87cm, 87cm by 123cm bow front and 60cm deep.
<Nice size tank.>
The options I currently have are 1 x 250W, 1 x 150W or 2 x 150W all with electronic Ballast and 2 x 24W T5 Actinics, I know lighting does have a lot to depend on the species kept. I do have a couple of soft and hard corals with a bubble tip anemone, tree polyps and some mushrooms, but would love to keep a clam at some point.
<The tank is a little long (48") to go with one 250, would be much better with two 175 watt halides. If you went with 14K lamps, you really wouldn't need the actinics unless you like the effect. If actinics are used, then I would use 10K halide lamps. With the depth of your tank (24"), the 150 HQI's will be cutting it close.>
Any advice will be of great help.
Cheers
<Good day my friend. James (Salty Dog)>
Wayne

Distance MH 10/9/08
Good Morning crew!!!
<Hello.>
I have a ? for the crew. I'm currently running a 10 gallon nano with an 150 watt 14000 k HQI lamp. And it sits 4 inches off the top of the tank. The temp is at 79.5 and the corals are doing great. But I was wondering the colors were looking a little better when I got them from my LFS. They have the same lighting but they hang them up much higher. Do you guys think I should rise my lighting up 1 to 2 inches off the tank so I can get more color off my corals???
<I would raise it up, for other reasons. This light this close can shock corals.>
Do you think it’s too close to my tank???
<Yes.>
Any help would be a great help.
<The coloration on your corals has no guarantee with any given lighting. The color you see in the LFS my change over time, even if the coral is not moved and stays there under the same conditions.>
Thanks
<Welcome, Scott V.>

Lighting, MH in Canopy 9/21/08
I currently have a 125 gallon semi-reef with compact fluorescent lighting. I would like to upgrade to Metal Halide but I only have about 5" between the top of the tank and the canopy (and would rather not build a new one). Am I stuck with what I have?
<There are other options.>
Any suggestions on other lighting options?
<Well, the question is what you are trying to accomplish, what livestock additions do you plan to make that needs more lighting? That being said you could fit MH into the canopy, but I surely would not. Issues are heat buildup (with fans can be controlled), light spread (negligible in the front to back span of 125’s), heat transfer to the tank (can be very significant) and the fixture/bulb getting splashed (it most certainly will in these close quarters). If you plan on obtaining livestock that requires more lighting, do consider either adding more PC’s or switching to T5’s. Either can keep a myriad of corals. The T5 fixtures definitely get my personal nod, although it may not be worth while if you already have PC’s, depending on how much you now have and how much you will need. If you would like to go MH, it can be done depending on the look you want. In the past I have had the same issue and simply mounted some pendants above the canopy, while having cut out the top of the canopy beneath the fixtures. Up to you and your taste!>
Thanks.
<Welcome, Scott V.>

Placement Of 1000 Watt Metal Halides? (On a 180g tank…say it isn’t so!) – 09/16/08
WWM Crew,
<<Hey Joe>>
Thank you for all of your work in putting together this incredible site.
<<Is quite the collective effort…on behalf of everyone…you’re quite welcome>>
I have been involved in the aquarium hobby for about 3 years and may have learned more in that time from this site than from all other sources combined.
<<High praise indeed!>>
I am in the process of upgrading tanks from an 80 gallon reef tank to a 180.
<<Congrats>>
I have everything else figured out but I am still working on my lighting needs.
<<A highly variable application…but as we so often state…try to base your decision/selection on the “needs” of your livestock. Something much easier to do if you happen to “specialize”>>
I have a 4 bulb 6' VHO fixture that I am going to use for actinic lights in the front half of the tank.
<<Mmm, I would split these between the front and back for a more uniform cast/appearance>>
I am planning on putting 2 x 1000 watt 10,000K halides in the back half of the tank.
<<Okay Joe, I have to ask…is this a joke? A test? Aside from the initial expense of the fixtures and the fact that this is WAY MORE light than this 180g tank needs/can use, for anything you might keep…the heat output is going to be tremendous (will likely overheat the room as well as the tank), as is the operating costs>>
My question is as follows:
How high from the surface of the water would I need to keep such high intensity bulbs in order to keep from frying my corals?
<<This is largely a function of the reflector (quality/effectiveness), but with these lamps, no closer than 24” and maybe as much as 36”…a huge waste my friend, go with a smaller lamp size. 250w would be adequate in my opinion…but you could use 400w bulbs/fixtures if you wished. And do so much more safely and economically than with the 1000w setup>>
I would like to keep the lighting system no more than 18" from the surface with 12" being more ideal but I don't want to scorch anything.
<<Not possible or practical in my opinion. You definitely need to reconsider your MH wattage choice>>
Mostly I will be keeping SPS corals and clams in the top sections of the tank with some LPS and soft corals in the bottom half.
<<Then go with a 250w bulb/ballast combo coupled with a good reflector (e.g. – LumenMax or similar) positioned 8”-12” above the surface of the water…and save yourself a lot of headache and unnecessary expense>>
Thanks for your time.
Joe Marchetti
<<Joe… There are systems many times larger than yours that don’t employ anything larger than 400w metal halide bulbs. You don’t need or want 1000w MH on a 180g tank! I very strongly suggest that you not proceed with the application you describe. Read/re-read the info we have available (start here and continue among the associated links: http://www.wetwebmedia.com/marlgtganthony.htm ) and reformulate a better/more practical lighting plan. Regards, Eric Russell>>

MH vs. HQI? What is the difference? 08/14/2008
I often see MH and HQI used very similarly but once in a while I see that one is better than the other. Can you please help me understand the difference between the two? I thought I read that HQI is a subset of MH, is so, what do we call the non-HQI MH bulbs? My perspective is someone building up a 175g 25" water depth tank that will eventually be
home to anemones and perhaps corals.
<<In basic terms, HQI is just a type of metal halide bulb. Commonly, there are two types of halide bulb. Single end which are mainly called a "mogul" fitting, and the HQI bulb, which is a double end fitting.>>
Thanks
Joe
<<Your plan of a tank sounds superb, Joe. Hope this helps. A Nixon>>

Ballast on timer? – 6/4/08
Hello,
<Hello!>
I purchased a Coralife lighting system , 2 MH and 2 CF actinics combo, should I also put the ballast on timers or this should be on all the time?
<The MH lights do not have a toggle switch on the hood; the switches on the ballasts are for the lamps. Leave these switches in the ‘on’ position, and plug the ballasts into a timer.>
Also, aside from fans .... drilling holes (for heat vents) at the top of canopy (12" high) a good idea ?
<Some sort of ventilation will be necessary. Usually this is accomplished by slotted vents on the ends of a canopy which fans pull air through. I imagine the same effect can be reasonably imitated from above, although active evaporative cooling may be less.>
Please advise.
Thanks/Jun
<You’re very welcome. Benjamin>

Re: Ballast on timer? - 6/4/08
Thanks for your quick response,
<No problem!>
ok...now...there are two plugs that are attached to the hood, according to the instruction one of those are for the MH the other one for the CF ... which one controls the MH , the switch from the ballast or the other plug?
<The ballast>
should I also plug that on timer as well? is the MH getting it's power on the ballast or from the cord that is attached on the hood? or both?
<If this is the Aqualight Pro (I assume it is, based on the description...I could be wrong.) then the two plugs from the hood itself are for the CF and moonlights. The ballasts are attached to the four prong cables, and power the MH lamps>
(I know) this is really confusing me as the instruction that comes w/ it doesn't really explain very well the functionality of each.
<Understood>
Thanks again/ Jun
<Benjamin>

Lighting issue... MH fixtures vs. saltwater    5/2/08
Dear Bob,
<Josh>
Thank you for being there for us.
<Welcome>
My question has to do with lighting and tank covers. I imagine that the issue I am having will become more of an issue as the "all inclusive" fixtures become more popular. Ok so here goes.
I have a 70 gallon Oceanic Tech series tank. The tank is open top by design.
I purchased an Outer Orbit HQI/T5HO fixture(2 - 250W MH and 4- T5HO fluorescents'). When I was shopping I also entertained the Coralife version of the fixture as well.
I was running the fixture for some time and then I started to get some flickering. Over the next month or so one of the halides blew out. It basically fried one of the connectors on the bulb and the associated socket). Upon further investigation, it seems that rust/corrosion was the cause. I contacted the mfg and the first thing they asked me was this over an "open top" tank. They led me to my owners manual which does state that this cannot be used over an open top tank.
<Mmmm>
Being an avid hobbyist, I frequent many fish/pet shop. Everywhere I go both the Coralife and Outer Orbits fixtures are in use over open top tanks. In fact if you look at any of the pictures that Oceanic has for their Tech Series tanks, is shows the Coralife fixture sitting on top of the tank.
Since my fixture encountered issues I downloaded the owners manual for the Coralife fixture. Sure enough they state the same, "the fixture is for use over covered aquariums only". Yet there it is in the picture over with the mounting legs just inches above the water on the open top tank.
<Seems a bit disingenuous>
It has been about 6 weeks since I got my fixture straightened out. I have my fixture sitting 9" above my (still) open top tank. I was inspecting my HQI' and sure enough I am starting to see rust again. Any suggestions. I do feel rather mislead by advertising at this point. Everybody that I speak to in pet shops claim they have not had any issues with this. Is my only option is to cover my tank? This totally defies the form and function of this tank as well as my beliefs. Are all HQI bulbs subject to this rusting/corrosion problem? Can you suggest a workaround? Thanks again.
Josh
<All lamps will suffer from corrosion with salt, water exposure... there are some preventative measures (shields/cowlings, lube on the threads....) that can be employed that will help to varying extents, AND reducing the amount of splash, spray (from discharges, bubbling....) in and around the lamps themselves helps tremendously. I encourage you to write the larger etailers here (Champion, Hamilton, Hello-Lights...) and ask re... it may be best to either raise the fixture up higher or look to "enclosed" pendant MH's. Bob Fenner>

HQI versus mogul Differences 1/24/08
Hello, Crew. I hope all is well with you.
<It is, hello Dan.>
I've been doing extensive research concerning MH lighting, specifically looking at double-ended (DE, HQI) versus single-ended (SE, mogul) bulbs and fixtures. I hereby proclaim myself "lost" and was wondering if you guys might be able to offer some bread crumbs leading me back to the trail.
<Sure.>
My main sources for information have been Reef Central forums, your FAQs, and then analytical data from Sanjay's site: http://www.reeflightinginfo.arvixe.com.
<Great site.>
Some things are clear: DE requires a glass shield while SE does not. Aside from this, I have heard many rumors/generalizations, and I have systematically invalidated them with Sanjay's data:
Generalization: DE are brighter than SE for the same wattage.
<Yes, but they do also consume more power.>
Result from data: Basically across the board, the SE bulbs have more PPFD than equivalent (same manufacturer, color temperature, and ballast) DE bulbs (using a shielded fixture on the DE). This is across manufacturers, ballasts, and wattages.
<This is something most do not pay attention to, you do generally come out ahead with an unshielded mogul than a shielded HQI.>
Generalization: SE bulbs are just DE bulbs with an extra shield and a different mount.
<From a user’s standpoint, yes. The HQI bulbs do fire different, hence the specialized ballasts for them.>
Result from data: The same bulb (same manufacturer, color temperature, wattage, and ballast) tends to have a very different spectrum in DE than than SE. For example, the SE XM 10K bulb has a huge blue spike that the DE does not.
<Yes, even thought they are manufactured by the same company, they are entirely different bulbs. You will also notice different spectra in the bulbs from ballast to ballast.>
Generalization: DE tends to be more "blue" than SE for the same bulb.
<With some manufacturers.>
Result from data: This is inconsistent but there are certainly specific cases (e.g. the XM 10K above) where the spectral data does not support this. There seems to be more correlation to ballast type (magnetic versus electronic) than bulb form factor.
<Hence your labeling generalizations.>
Another consideration is that the "better" reflectors, e.g. LumenArc III and LumenBright, are much more available for the SE bulbs. The former only has one fixture, the LumenArc Stealth, for DE bulbs, and the latter only accept SE bulbs. For SE bulbs there are many more sizes, etc.
<The HQI bulbs are becoming more and more popular, with commensurate increase in choices.>
Can you guys help me out here? What are your experiences? Ideally I'd like to do this (buying MH ballasts, bulbs, reflectors) once.
Thanks much!
Dan
<Dan, I have used many types and spectra of bulbs. I currently use mogul based bulbs for the reasons you listed above. They generally use less power, run bluer and yield more PPFD (unshielded). That is my choice, others may advocate for HQI, but both will work fine. Hope this helps you decide, Scott V.>

MH Spectrum Question 1/20/08
Hello Crew.
<Hi Andy.>
I have been searching WWM for an answer to a question, but I am not having much luck. I have a 110g display (48Lx30Hx18D). Lighting is by 2x250W HQI and 4x65W actinic PCs. The HQI bulbs that came with the unit are 20,000K. I don't mind the bluish color--in fact I like it (and I'm sure these bulbs are cheap and aren't truly 20,000K so they are probably whiter than they should be).
<Actually most of these bulbs are bluer than 20K!>
My question is whether I should replace these bulbs with ones that are 10,000K?
<If you want to.>
I know enough to know that 20,000K is not the best choice, as temperatures in the 6,500K-10,000K range are best for coral health/growth.
<Yes, exactly.>
I found many, many posts on WWM discussing spectrum under various situations, but none has really answered the question of whether 20,000K as the only MH spectrum is a bad choice. I have read posts stating that 20,000K bulbs are "fine" or "will work", or that the issue is really one of aesthetics. So my REAL question is, is 20,000K vs. 10,000K really one of aesthetics?
<Aesthetics are the main reason for running the higher Kelvin bulbs. The 10K bulbs provide more usable light, but lose the blue look that is so popular now.>
My corals--various mushrooms, a Lemnalia and a Kenya tree coral, pulsing Xenia, and a rose open brain--do not have high light requirements, but I know my tank is high at 30". Everything seems very happy under this lighting (everything other than the open brain was previously under HO T5s). I do not intend to experiment with SPS, clams, etc.
<With this livestock I would be happy with the 20K bulbs if you are in the growing category of people that like the blue look. Look into the 14K offerings if you want something in the middle.>
As always, thanks for the help.
Andy
<You are very welcome Andy. For more information on the various bulbs and useable light provided check out the site below by Sanjay Joshi. Happy reefing, Scott V.>
http://www.reeflightinginfo.arvixe.com/

Sunlight Supply Reef Optix 3... ballast  1/20/08
I won 1 of these reflectors in a raffle at a frag swap but it did not come with a ballast. I was wondering if it will run on any other ballast than a Blue wave 3.
<Yes it will so long as it’s a 150 HQI ballast.>
I really don’t want to spend as much on a ballast as those cost so if there’s a cheaper alternative could you recommend 1 if not ill just sell the reflector.
<Take a look at the Hamiltons. If you look around you can find them for under $100.>
The light will be over an oceanic cube 30 gallon which is used for nothing more than a frag grow out tank.
<Have fun, Scott V.>

Metal Halide Question 1/19/08
Hello,
<Hi Eric!>
I recently purchased a retrofit metal halide + pc setup for my canopy. The metal halide is 250W 12000K lamp and the PC are 2 x 32W. The thing is I only have a 30 gallon tank and realize that this is way, way too much wattage for this size of aquarium.
<Depends on what you want to keep. The wattage is more relevant in regards to coral placement relative to the light, not tank size. That being said, a 150 would be perfect.>
I got the retrofit setup for next to nothing and may just use the PC bulbs but I would love to use the metal halide so my question...am I able to purchase a 150W bulb for this retrofit setup. In other words, are there compatibility/safety issues with using a lower watt bulb with a 250W ballast?
<Yes there are issues. The bulb will probably light up, but it will not be a safe situation, as you will find out quickly. The bulbs need to be used with their respective ballasts. Also, unless you are talking mogul based bulbs (which are rare in 150W), the sockets will not match up either.>
Thank you for your help.
Eric Russell
<You’re welcome Eric. If you have the cooling capacity for the higher wattage, do consider the possibility of running one of the 20K or similar blue bulbs in the 250W. This will provide a dimmer bulb with less intensity. This may just fit your bill here. Also, since the bulb runs bluer you may be satisfied with the look of your tank and find yourself skipping the actinics altogether! By the way, nice name, I am sure you are aware you share the same name as a fellow crewmember/friend? Best wishes, Scott V.>

Lighting Question, MH fixtures f' 1/16/07
Hello,
<Hello.>
I've been looking at a whole bunch of different lights right now. My biggest concern right now is when I have to move I would like to have a lighting system with a stand so I don't have to hang them from the ceiling.
<OK>
I currently have (2) Reef Optix 3 HQI 150W reflectors, with 20K Radium bulbs. Blue Wave VII is running both of the halides. These currently hang from the ceiling. I would like to change to combination lighting, of (2) 150 watt halide bulbs and T5's for actinic. This way I get the PAR value of using 10K for the halides and either a range of 420nm or 460nm for the T5's.
<Good combo.>
I've been looking at the Current USA Outer Orbit 36" with (2) 150W HQI's with 4x39 T5's combination unit. My question is, the ballast for this unit is all internal, I'm wondering how good that ballast would really be and if you think I would have problems with it in the future.
<These are fine with the built in cooling fans.>
Also, if you would have any suggestions for combination units that you have heard good things about.
<Most the major manufacturers have similar systems that perform well: PFO, Sunlight Supply, Hamilton, Giesemann, Aquamedic, etc.>
My tank measures 36x 18x24. Thank You
<Welcome, Scott V.>
 

Lighting 110 1/1/08
Happy New Year!!!!!
<Hello Peter, happy New Year to you also.>
I had a question about lights. I am putting in a 110 gal tank that is 30" high and I am planning on using live rock and housing both soft and hard
corals. The reef store I am using is planning for 2 250 watt 20K metal halide lights with a retrofit reflector.
<OK>
My biggest issue is that the ballast is big and it would need to sit outside the cabinet. I like the blue shimmy on the water that is why I am using the metal halides.
<Me too.>
Some of the other lights I have seen on the net are a combo compact unit with 2 250w 20K HQI's with 2 T5s and a blue night light. The pictures show a small black ballast incorporated into the cord. So, are the ballast associated w/ these compact lights really that small?
<Without seeing the particular picture, I can’t say 100% for certain, but it sounds like you are describing the plug that many lighting fixtures use to connect to the ballast. A little square incorporated into the cord, not the actual ballast.>
Do you recommend these lights?
<If you have a canopy that you were going to put the retrofit kit into I recommend sticking with that. It is better suited for inside the canopy use and will generally cost you less.>
Is there one brand any better then another?
<Really depends on the bulb, ballast, look and bells and whistles you want. For the most part all the lighting fixtures out there work fine. Electronic ballasts tend to be more efficient, run cooler, and tend to be much smaller.>
Thanks so much for your help,
Peter Abbey
<Check out the link below. You can compare different bulbs and ballasts. Pay particular attention to bulb spectrum, ballast type, power usage and efficiency. Welcome, good luck, Scott V.>
http://reeflightinginfo.com/Selection/EquipSelect.aspx

Interchangeability of Components of Corallife Aqualight Fixtures – 12/18/07
Thanks for your help.
<<Quite welcome>>
I have a rather disturbing situation here...
<<Oh?>>
During the conversion to my new 180 gallon system I discovered that the 48" Corallife Aqualight Pro system that had the two 250W Metal Halides has them running off of 150W ballasts (or at least they're labeled as 150W on the stickers).
<<Hmmm… It came to you this way, new, in the box (sealed)? I suppose it’s possible the ballasts were mis-labeled. Or maybe the even bulbs are mis-identified…though I’m assuming you know the difference, and can differentiate between the two bulb and/or bulb-holder types. Have you been using this unit since our last exchange back in July? Have you noticed anything/had any problems with the performance of the unit? I would expect 250w bulbs to burn dimly/flicker/make noise if run on 150w ballasts…if they fired at all>>
I bought it new from the store and it has always had 250W bulbs and I've never replaced the ballasts, so I know I didn't mix 'em up.
<<Odd…and a bit scary>>
My new 72" Corallife Aqualight Pro (with three 150W lights) has the EXACT same ballasts.
<<Mmm, okay>>
I'm running both lighting systems on the new tank.
<<I would stop using the one until the mismatched ballast/bulb issue is resolved>>
What do you think I should do here.
<<Couple things… If you bought the unit local, take it back and see if they will make an exchange (be sure to inspect the new unit In the store just in case this is a problem with a given “LOT”). If not, contact Corallife and explain the issue to see what they will do>>
Is this something I should be concerned about?
<<I would be, yes. If the components are truly mismatched, there is an increased potential for fire and more>>
Thanks,
Eric
<<Happy to assist…and please do let me know how things go with this. Regards, Eric Russell>>

Was Euphylliid allelopathy, now halide recommendation 9/13/07
Hi Bob,
<Tom>
Thank you for the suggestion to check out Sanjay's work. If I'm reading his data right, I should see about a 16% increase in the PAR value by switching to the Ushio 10K 250W bulb. Not a huge increase, but may be worth trying the Ushios at the next bulb rotation.
<Yes>
Interesting side notes, I learned that going with an electronic ballast (e.g. Icecap) appears to reduce the bulb's PAR value, compared to magnetic ballasts. And that HQI ballasts are the most efficient in terms of PAR per watt, followed by std. magnetic, then by electronic.
<Ah, yes>
Sanjay's work indicates a much greater 56% PAR increase if I were to switch to the Ushio bulb and upgrade to a PFO HQI ballast. I currently have a standard magnetic ballast. But I couldn't find data on comparative bulb life. In your experience, should the HQI ballast lead to a noticeably shorter bulb life, since it basically overdrives the bulbs?
<I don't think the trade-off is bad... i.e. the lamps effective life-use is not appreciably diminished compared to what is gained in PAR photonic energy. BobF>
Tom

Unshielded DE Metal Halide Bulbs...Danger Will Robinson!!! – 09/10/07
WWM Crew,
<<Rick>>
Your FAQs and dailies have been an invaluable resource. My tank and I thank you for the knowledge.
<<We’re pleased you find the site useful>>
I had two Current SunPod HQI metal halide units (14k w/ 150W, total of 3 original bulbs). When I upgraded to a larger reef tank, neither of the units fit the tank. Rather than purchase a new unit, I removed the contents of each fixture and integrated them into a wooden DIY enclosure.
<<Neat>>
The enclosure utilizes the existing fans found in the original units, as well as an additional and larger fan. The enclosure hangs approximately 13 inches off the tank, with the halides approximately 18 inches off the tank. The tank is adequately covered so as to prevent water splashing onto the bulbs, reflectors or ballast.
<<Mmm, usually little concern with this...better to let the tank “breath” in my opinion>>
The fixture has operated safely for two months now, but I fear the UV/radiation dangers that may be posed by this setup.
<<Oh?>>
My concern is that I have not included any glass/UV shield below the bulbs.
<<Yikes! Yes, this is a “danger”...to you, your livestock, et al!>>
Is this a valid concern?
<<Indeed...please do install UV shields over these double-ended bulbs. Special “UV” glass can be obtained, but simple float glass from the hardware/home store will also afford some protection...or utilize the shields that surely came with the original fixtures>>
Could the bare light exposure be harmful to humans or corals?
<<Not “could be”...”is”... The fact you have the tank “covered” to prevent splash is probably why you haven’t “cooked” your livestock before now...but the potential for damage re, as well as to you and your family, is very high. I have seen “cracked” Mogul-base bulbs do damage to livestock...I can only imagine how hazardous these completely exposed/unshielded DE bulbs must be>>
If so, how can I remedy the situation?
Thank you,
Rick
<<Rick, I can not stress enough the potential danger this unshielded fixture poses to you and your family’s’ health/eyesight. Immediately discontinue use of this fixture until adequate UV shields can be fashioned and fixed in place. Regards, EricR>>

Re: Unshielded DE Metal Halide Bulbs...Danger Will Robinson!!! – 09/11/07
Eric,
<<Rick>>
Thank you for replying promptly. I will discontinue use of the fixture immediately!
<<Excellent my friend...really is best for the continued good health of all>>
I am interested in replacing the fixture today. I am debating between either another Current HQI unit w/ 14k, 3 x 150w (with the UV shield intact :)) and a T5 setup.
<My personal preference is always metal halide...but the T5 technology is impressive I’ll admit, and I have seen photos of some spectacular European tanks utilizing this lighting exclusively>>
My setup consists of 60 x 24 x 18 (125 gallon tank)
<<Mmm, closer to 112g actually>>
and 45 gallon refugium.
<<Very good>>
I keep a variety of corals including a bubble coral, frogspawn, hammer, zoanthids, clams (Tridacna derasa and T. crocea), Montipora and a bubble tip anemone (on his own island, away from the corals).
<<Ah yes...the usual volatile (and popular) mix>>
Do you know of any specific T5 fixtures that can accommodate the corals I am keeping?
<<Hmm, finding a 5ft T5 HO (80w bulbs) aquarium fixture may be a challenge, though Specialty-Lights.com does carry the 5ft bulbs (Giesseman Power Chrome) if you can find a suitable “commercial” fixture. But then, you can likely get away with a 4ft T5 HO (54w bulbs) fixture on this tank. A six bulb fixture as a minimum, but eight would be better...considering the Anemone. Check out fixtures by Tek Light and Aqua Medic on the high end...for something functional but not so “pretty” (or expensive) look at the Sun Blaze fixtures>>
I would love to eliminate the heat issue caused by halides and wouldn't mind bluer lighting.
<<Don’t be fooled, the T5s can get hot enough to nearly fry an egg...any “heat issues” you are experiencing will not likely just “go away” by switching to the T5s...at least not if you use as many bulbs as needed here. As for “bluer” lighting...I recommend you not exceed a 60/40 ratio of 6500K-10000K vs. Actinic...and 70/30 would be even better>>
Thanks again!!!
Rick
<<Happy to share. Eric Russell>>

Question about lighting for a 30 inch deep tank, MHs   8/20/07
Hello and I hope you are having a good day. Thanks in advance for answering my question. Here's my tank specs:
110 gallon 48"X19"X30" tank with 20 gallon refugium set up May 2006
Current Extreme T5 lighting with 8 X 54 watt bulbs (2 actinics, 2 10K, 2 12K, 2 20K)
200 pounds of mixed Fiji, Tonga, and Caribbean live rock
Aqua C 120 EV in sump (an excellent PS by the way, thanks to your advice)
4 Maxi-jet 900, 2 maxi-jet 600 in tank for circulation
Mag drive 750 return pump from sump, skimmer, refugium area
I use an ATO system with addition of Kalkwasser to top-off RO/DI water, I have about 3 liters of evaporation per day
Fish and invertebrate list:
1 yellow tang, 1 maroon clown, 1 bicolor Pseudochromis, 1 coral beauty, 3 blue/green Chromis, i cleaner shrimp, 1 CBS, 1 sand sifting sea star, 1 large brown brittle star, 30-40 scarlet and blue leg hermits, 1 rose BTA at middle of tank, 2 Condy anemones at bottom of tank,
<Trouble if/when these actinarians meet>
several species of buttons and zoos placed in the middle of tank, some porites placed close to top, 1 open brain placed towards middle of tank, pumping xenia at bottom of tank.
Tank parameters:
SG 1.025-1.026
pH 8.2-8.3
Alkalinity 3.5-4.0 meq/L
Nitrite 0
Nitrate undetectable
Ammonia 0
Calcium 350-400
I like the color and appearance of the tank except I want the glitter effect of the MH. Also, I get all of my corals from the LFS that uses MH fixtures. Whenever I bring my corals home, they don't seem to open like they did at the store and don't look as healthy (my thinking was that they need to get used to my lighting). Some of my zoos will close up and appear almost like they are bleached even after moving them around to different levels of the tank. My open brain has really opened up and has become almost translucent (I can see the skeleton through the tissues). The brain does extend its feeder tentacles at night and shrinks up. The anemones, xenia, and porites are very healthy and look great. I have a lot of xenia to give away if anyone wants any. I have given the zoos and brain plenty of time to acclimate (I have haven't added anything new for about 4 months).
OK, now for the questions. I was considering changing to MH lighting because I really like the glitter and am thinking about adding some SPS, LPS, and a clam or two.
<Do read re the needs, compatibility of all you have, want to add... ahead of tossing in more>
Since my tank is 30" deep, do I need to get 2 250 watt or 2 400 watt fixtures?
<I'd go with the 250's myself... sufficiently bright, good-looking w/o adding even more heat, higher electrical bills>
My main concerns are heat and UV transmission. How high off the tank should these pendants be hung?
<Posted...>
I was thinking around 6-8 inches above tank. I don't have a canopy and I don't want light going all over the room. I like the Hamilton Reef Star pendants and am seriously considering them.
<Good units in my estimation>
I also want a all-in-one unit with remote ballast and plug-and-play capability and it appears that the Hamilton pendants are the easiest way to go for me. Since these will be my only fixtures (no actinics), I want to use 14K or 20K MH bulbs (I am leaning to the 14K bulbs).
<Should be fine>
I am confused over the difference in the DE HQI and the mogul bulbs other than the price and some say that the DE bulbs are more efficient.
<Also posted...>
Do you think there is much difference in performance of the Hamilton reef star DE HQI and the Hamilton reef sun mogul base MH fixtures of the same wattage? I was leaning to the 400W Dual Reef Star fixture (total 800W) from aquacave. Do you think that the addition of the MH fixtures would improve the appearance of my zoos? Thanks for your time.
Kevin
<Oh yes... Please read here: http://www.wetwebmedia.com/marsetupindex2.htm
the last few trays. Bob Fenner>

Metal Halide Fixture Choices vs. Over-Heating Issues – 08/10/07
I have looked through the articles posted and can't find an answer to my question so here it is. I'm looking for MH for my 240G set up. The tank is 72x30x25. I am planning on 3x250w MH supplemented with T5's.
<<Okay>>
My question is what is the best type of lighting to go for?
<<Mmm...what is it/what effect do you wish to achieve?>>
I'm putting these fixtures in a canopy. I was very keen on the Lumenmax3, but fear they might have a heat build up.
<<This is a very nice reflector/pendant, and no more likely to cause heat problems than any other...and heat “will” be an issue in this canopy regardless of the lighting fixture>>
What I like about them is that they are compact and have the UV glass shield.
<<I can think of some others with the same aspects...but this pendant is a fine choice>>
I have also read reports on the vented Lumenarcs, do you need UV glass under them if they are in a canopy? ( I guess they would still be dangerous when you open the hood).
<<Indeed you do, any time you are using the “double-ended” bulb fixtures...and the hazards of not doing so extend to your livestock as well as to you and your family>>
I have also got a fairly large (1300 cfm) <fan> that I was going to suck hot air out and have fresh air supplied by the A/C ductwork (or outside air in the winter).
<<Sounds like a good plan>>
I'm still a little confused as to what would be the best setup with regards to minimizing heat build up.
<<I think what you have outlined should be fine, though you may have to experiment with the size/number of fans and vents to handle the overheating issues>>
Thanks in advance for your help.
Olly
<<Happy to assist. EricR>>

Re: Metal Halide Fixture Choices vs. Over-Heating Issues - 08/11/07
Thanks I appreciate your reply.
<<Quite welcome>>
What would be the minimum distance from the bottom of the reflector to the water?
<<Whatever places the “bulb” within a general range of about 8” – 12” from the water’s surface>>
I have a 12" canopy, and say the water will be about 1" from the top of the tank, and that most fixtures are between 6" and 8" that will only give me about 5" -7" of clearance. Is that sufficient?
<<Considering the bulb will be a bit higher within the fixture, yes, this will likely be fine>>
Thanks again,
Oliver R Oakley, PhD
<<Happy to help, Eric Russell>>

Metal Halide Fixture placement problem  7/28/07
Dear Crew,
I need a quick response very fast please!! I just received a SunPod 48" 2x250watt 14k metal halide fixture from Champion Lighting. I do not want to hang this fixture. I have a 90 gallon tank with a canopy measuring about 50-51 inches long. My current lighting is a Orbit 48" 4x130watt Power Compact. I used the legs to mount that on the top of the canopy which I keep open. When I tried to place the new fixture on the top of the canopy with its mounting legs, it fell short about 3inches. It will only fit when I remove my canopy and place directly on my tank. If I could place the fixture on the of the canopy the distance from the surface would be 12 inches. But, since I can't...it is more like 3 inches when placed directly on my tank. Is there any solution this problem?
<A new canopy or fixture...>
I need to find a way to place the fixture at least 10 inches above the surface and it doesn't fit on my canopy. Once again I do not want to hang this fixture unless is last resort.
Please send advice! Thank you guys/gals so much!
Peter Choo
<Please see WWM re Canopies... MH fixtures... Bob Fenner>

Interchangeability Of Components Of Coralife Aqualight Fixtures – 07/19/07
I'm setting out on a new adventure... a 180gal reef tank.
<<Cool!>>
It will replace my 55-gal reef tank (all residents will eventually be transplanted to the new, larger tank). I've worked out all the details, pricing, etc... except for one thing. I have an opportunity to get a great deal (less than half price) on a Coralife Aqualight Pro.
<<I see>>
It's the 72" fixture with three 150W 10K's.
<<Should do nicely>>
The tank will have these residents:
Galaxea
Pagoda Cup
T. Crocea
T. Derasa
There are several others, but these are the ones in need of the most light by far.
<<Okay>>
Also, they would be kept high in the tank (except the T. Derasa clam, he likes his sand).
<<Indeed>>
Questions:
1) Will three 150W 10K's be enough? (My math says no since that's only 2.5Wper gal).
<<The “watts per gallon” logic for determining lighting requirements is really a very poor method in my opinion. There are so many factors that determine “what is adequate”...e.g. water depth, water clarity, requirements of the individual organisms, color temperature, feeding, etc. If you were planning to keep shallow water Acroporids I would suggest more wattage; and even then not because the corals couldn’t live under your planned configuration, but because I think they would “color” better under the higher wattage lamps. But with what you have listed, the 150W lamps w/10,000K bulbs will be fine>>
2) If I take the two ballasts and bulbs from my current tank's Coralife Aqualight Pro (48" fixture with two 250W 10K's and ballasts to match), could I replace two of the 150W ballasts/bulbs with the 250W ballasts/bulbs?
<<You could...but you will also have to change out the bulb brackets/holders as these for the differing wattages are not compatible/interchangeable>>
Are the internal components of the fixtures compatible or would I burn something out?
<<Being from the same manufacturer it is highly likely they are virtually identical on the inside but for the ballasts/bulbs/brackets>>
3) If what I discussed in question 2 is a possibility, would the resulting 650W total be enough for these residents (3.6W per gal)?
<<More than, yes>>
If not, what should I shoot for? Any brand/model recommendations?
<<I think you are fine with the 72” fixture mentioned>>
Thanks so much!
~Eric
<<Happy to assist. EricR>>

Do I “Need” That HQI Ballast?...Mmm, Nope – 06/20/07
Dear WetWebMedia Crew,
<<Hey Eric!...EricR here>>
First and foremost I would like to thank you for all the information provided on your site.
<<Quite welcome...is a collective effort>>
I have had my tank running for over a year now and much of my success can be attributed to the information I have obtained from your website.
<<Redeeming to know>>
My question is regarding a PFO Metal Halide ballast.
<<Okay>>
I recently upgraded from Power Compacts to a 250-watt PFO HQI Metal Halide pendant.
<<Quite a change, eh? Metal Halide lighting is my fave for most any marine aquarium application>>
When I ordered the ballast I ordered the PFO 250-Watt Single Metal Halide Ballast and not the 250-watt HQI Single Metal Halide Ballast.
<<Shouldn’t be a concern>>
Should I return the ballast and get the HQI version?
<<Just for the sake of having the HQI?...No... Basically, the differences between the ballasts equates to the fact the HQI ballast will let you run what many consider more efficient, higher output (Watt for Watt, Kelvin for Kelvin) double-end bulbs, whereas the ballast you purchased will be restricted to the single-end/Mogul-base bulbs>>
There is a bit of a cost difference between the two,
<<The bulbs too!...usually>>
so ultimately I would like to stick with the one I have if possible.
<<The “single-end bulb” ballasts are used by many hobbyists over a wide range of applications, I’m sure the “ballast in-hand” will serve your purpose just fine>>
Thanks again,
Eric
<<Happy to assist. EricR>>

400 watt MH ballast   6/5/07
Hello Crew,
<Chad>
Thanks for this portal to aquatic information and more. I was recently given two 250 watt and a 400 watt MH ballasts that came out of a local warehouse. These are the magnetic type of ballasts. I'm wondering if these will be satisfactory for a DIY canopy that will be going over a 120 gal reef system. What mogul based bulbs would you suggest for a "mixed garden type reef set up? Do you fore see any additional hurdles using these types of ballasts?
<Mmm, just the usual heat issues really... The lamp choices for particular mixes of life are posted... Please read here: http://www.wetwebmedia.com/marsetupindex2.htm
The bottom of the page… Marine Lighting… the MH articles, FAQs files.
Bob Fenner>
Thanks you kindly,
Chad

Can I Place Metal Halides 3” From The Water’s Surface? – 05/30/07
Hello Crew,
<<Hi there Matt!>>
I am setting up a 60-gallon Anemone tank and have a question.
<<A specimen tank?...excellent>>
I have 2 Mogul-based halides and my canopy isn't very tall.
<<I see>>
I am wondering, what are the drawbacks with mounting metal halides close (3-4") above the water?
<<Hmm...possibility of breakage from splashing, and heat issues mainly>>
I have a chiller so temperature isn't a concern.
<<Ahh, okay...but I would still provide for some ventilation to the hood>>
I have searched through the forums and cannot find the answer to this question.
<<Guess there will be one now! [grin]>>
Thank you for consideration.
Matt
<<Since you have the issue of heat transfer covered, your greatest problem will likely be from splashing water as stated (perhaps you can fashion some form of splash shield)...this, and the fact you will need to clean the bulbs of crusting minerals more often...otherwise you should be fine I think. Regards, EricR>>

Inexpensive MH Lighting System...Buyer Beware? – 05/25/07
G'day Crew,
<<Hello Dan>>
Just a quick one for you, was wondering if you know anything about the SunSun brand of metal halide lights?
<<Mmm, nope...Hadn’t heard of these before now>>
They have units here 3 x 150 W + 2 x T5 HO fluorescent + LED moonlights for A$500.
<<Ah, yes...looks to be a bit over $700 US from what I can find here>>
That’s ridiculously cheap compared to what you'd pay for a similar set up at a LFS.
<<And maybe reason enough to be suspicious of the quality...These are likely a “knockoff” and “may not” prove worth your hard earned money in the long term>>  
I did a search on your site but couldn't find anything.
<<Indeed...I think this brand is a fairly new arrival>>
Anything you could let me know about them would be great.
<<I strongly suggest you ask about on the BBs (Reef Central/Reefs.org) and see if anyone has purchased/has some working knowledge of these lighting systems.  There have been some really “inexpensive” systems/components pop up lately, and to put it bluntly some of these are simply “crap” so...buyer beware!>>
Dan in Sydney
<<EricR in SC>>

SunPod HQI    5/7/07
Hello WWM Crew,
<Wesley>
I've searched through your site and can't find the answer to my question:
Whether the Current SunPod HQI 300w fixture requires an UV shield over the aquarium.  I see that this product has a 'splash lens" protecting the bulbs.
<Mmm, yes... the lamps themselves are provided with UV shielding... but important to keep water from splashing on these, all other (especially hot and that get hot) lamps...>
I have a 50g acrylic aquarium with what I assume is an acrylic cover that can be placed over the two holes (cross braced).  However, I currently am using a 2x92w pc fixture on the same type of legs my new fixture will use.
With the cover on, my tank temp peaks at 82 - 83 during the day, without the cover it only gets to 80.  When I get my new fixture in will I need to make use of the cover?
<Maybe...>
Finally, in order not to shock my corals, how long should I leave the HQI lights on for the first few days?
<Posted... better to either shade the new light for intensity or move the fixture "up" here...>
I will not be able to supplement the lighting with my pc bulbs since there is not enough room.
Thanks,
Wesley
<Please read here: http://www.wetwebmedia.com/acclimcoralslight.htm
and the linked files above. Bob Fenner>

Upgrading and need new light   3/8/07
I just discovered your site a couple of days ago and boy am i glad i did ! You site is awesome and it saved me from making a big mistake!
<Ah, good>
I  just  purchased a new tank and am gathering up the rest of the equipment. My focus right now is on lighting. I was thinking about a strip that includes 3 250w 10k mogul basmetal halides and 2 140w actinic VHO with a magnetic ballast or i can choose HQI MH with electronic ballast.
<I'd skip on the actinic>
The tank i got is a 210gal @ 30" depth. I have been reading scores of the questions you have answered for others, but i seem to still be unclear about whether electronic ballast is a good thing or a bad thing.
<What would Martha Stewart say?>
The fixture i have been looking at is sold by Aqua Universe on e-bay. There are no brand names for the ballast or bulbs. I understand that if these bulbs don't live up to expectations i will have greater choice in replacing them if i have an electronic ballast and that it would be more efficient in electric usage. On the other hand one or more of you has recommended against the electronic ballast for reasons I'm not quite clear on. Do you know anything about this setup from Aqua Universe?
<Mmm, no. However... the actual gear used in such lighting packages is made by an astonishingly small number of companies... re-labeled...>
Are my choices (assuming good fixture/bulbs) adequate for say a nice clam?
<Yes>
Are HQI bulbs generally superior to Mogul based?
<Mmm, not IMO>
I'd also like to hear your opinion on the JEBO protein skimmer.
<Mediocre design, construction... our collective input on skimmer selection is posted>
Thank you, the volume and quality of advice and references that you and some of you online contributors dispense is amazing. I wish i had found this forum long ago.
David McElvain
<Glad that we have found each other now. Bob Fenner>

Lighting Upgrade (Sometimes Too Much?) – 03/07/07
Hi WWM Crew
<<Hello Claudio!>>
After a year is time to renew some bulbs and I am considering upgrading the ballasts to electronic in order to save some on energy and improve on efficiency.
<<Cool...I use electronic ballasts myself (IceCap)>>
My current lighting set up is:
4 * 250W 10000K, (3pm to 11pm) mag ballast
2 * 400w 6500K (5pm to 10pm) mag ballast
4 actinic VHO 110w each on an IceCap 660 e-ballast. (1pm to 12midnght)
<<Ok>>
Light is ok but really a little bit too yellow for a 94"*24"* 39" tall (2.40*0.70*1.00 meters tall)
<<Mmm, a matter of opinion/aesthetics...am sure the corals don’t mind...>>
I was considering changing the 4 VHO to power compacts 96w each double actinic.
<<I would stick with the VHOs mate...more efficient with better bulb life over PCs...in my opinion>>
Changing the 4 * 250W for one central 1000w 20000K on Lumateck e-ballast
<<What could possibly be your reasoning for this?  Though the intensity will be insane, you will only be able to focus the light in a small area as compared to the four 240w fixtures spread over the tank.  Not to mention you will likely “burn” your corals unless you are very careful about acclimating them to this new light intensity...and even then, it may prove too much for many species depending on their placement...even with the 20000K bulb (which are too blue but for deep-water species tanks...in my humble opinion>>
Changing the 2* 400W for 2*400W 14000K also on Lumateck.  The choice on ballast is motivated because I have a 240volt 2 phases electric wiring in place for the lighting that saves on energy consumption over the regular 120 single phase and this the only company that I found over the internet that sell 1000W e-ballast.
<<Hmmm...I’m not an electrical engineer...and this is a moot point for you/your country...but I do believe it is a common misconception that a 240-volt appliance uses “less” electricity than a 120-volt appliance with the same electrical “draw.”  All things being equal, a 1000-watt bulb will consume 1000-watts...regardless of the line voltage it works on.  240-volt circuits do have advantages over 120-volt circuits in some applications, but I’m skeptical as to the 240-volt service being more “economical” to use than the 120 volt service...again...all other things being equal>>
The change for one 1000w instead of 4 * 250w also is motivated on efficiency and light penetration, because when moving to a 2000K I will lose some PAR and I want to compensate with intensity.
<<A misguided venture in my opinion.  I truly do believe you will find the 1000w metal halide bulb to be more trouble (smaller lighted “foot-print”, concentrated hot spot, over photo-saturation of your corals, limited bulb selection, etc.) than you are bargaining for.  It’s your call in the end...but I would like to urge you to reconsider leaving the 250w fixtures in place and replacing those bulbs with 14000K bulbs like you are doing with the 400w fixtures.  The four 240w fixtures coupled with the two 400w fixtures, all utilizing 14000K bulbs, should be “plenty” of light for this 39” high tank>>
Please all possible comments are welcome.
<<I hope you find them of some benefit>>
Thanks in advance to all.
Claudio
<<Quite welcome.  Eric Russell>>

Re: Lighting Upgrade (Sometimes Too Much?) – 03/08/07
Many thanks for your comments,
<<You’re quite welcome Claudio>>
One more question, my lights are very high above water level, about 24 inches... Any comments (is really a lot of work bringing them down)?
<<Hmm...8-12 inches would certainly be better...but if not possible/practical then perhaps switching the 250w MH fixtures to 400w fixtures would be best>>
I will stick to VHO, same price + or less, less work.
<<Excellent>>
Changing to 14000K, what Brand of bulb do you suggest...
<<I am particular to the Ushio 14000K bulbs as my first choice, with Hamilton being my second choice (in this color temperature).  But there are many new 14000K bulbs popping up on the market that could/should be investigated>>
Ballast... ICECAP???
<<My personal fave, yes...and much to do with their reliability, customer service, warranty, flat-fee repair service regardless the age of the ballast, et al.>>
Any other?
<<Several choices (ARO, Coralvue, Blueline, etc.), you can even opt for a ballast sold “outside the trade” such as from here (ballastwise.com)>>
About lighting schedule do you like what I have now???
<<I like the fact that you stagger the lights...but I prefer a “duration” schedule closer to that naturally occurring in the tropics (12-14 hours).  It has even been suggested by some authors (e.g. Richard Harker) that “extending” the photo-period can compensate (to a point) for a low intensity output.  In other words...leaving all your fixtures at their current wattages (go ahead and change to the 14000K bulbs if you wish) and extending the photo-period to 12-hours “may” give you what you are looking for>>
Many thanks again, before spending money some time less is more...
<<Indeed so my friend...always best to research before you rush...  Regards, Eric Russell>>

R2: Lighting Upgrade (Sometimes Too Much?) – 03/08/07
One thing.
<<Hello again Claudio>>
About 240V wire vs. 120V , saving comes from the split load, actually you are consuming the same amount of Amp 1000/120 and 1000/240, but because you
are splitting in 2 phases of your regular household service, you have a lower consumption spike and therefore, your meter is charging a little less.
<<Hmm, interesting...as previously stated, I am no electrical engineer, I do/have done much my own electrical work to include installing/wiring new 200-amp service panels for my house and shop (all inspected and approved by the county after the fact, of course), adding new/extending existing circuits, etc.  But I have never worked with multi-phase circuits, other than to operate equipment (mostly in the military) that utilized such>>
Actually you meter charges you using the higher load of any phase, so the more balanced your consumption either in 2 or 3 phases of your electric
service the lower the bill.   Also because the ballast always transform electricity to 130 or 150V (depending on bulb MH, HS or HQI), transforming is always more efficient from higher voltage.
<<I see>>
I do not know if explained myself enough, some electrician will do a lot better,  English is not my main language, and spell checkers are not enough...
<<Ah, but you are doing fine...and anyone wishing to question/investigate this further will hopefully do proper research beyond our exchanges re>>
Thanks again,
Claudio
<<Always welcome, EricR>>

How High Should I Mount My Metal Halide Fixture? (Simple Question...Never A Simple Answer) - 02/17/07
Hey Crew,
<<Hello Samantha>>
Sorry, I searched the forums but couldn't find this answer.
<<Ok>>
It's not a very hard question (I HOPE).
<<Hee!...is what they all think...[grin].  The "difficulty" is generally due to the vastness of the category and the inherent limitations of this media...but let's press forward...>>
I have been running a fish-only tank for about 4 years and I want to try my hand at coral.
<<Most do...eventually>>
I have a 30-gallon tank but I’m' upgrading to a 65-gallon in a few months.
<<Excellent>>
I bought a 250W metal halide.  I know that normally a light is supposed to be kept 8-inches from the water surface, but that would be 8.3 Watts per gallon.  How far should I keep my light away from the surface?
<<Generally speaking, metal halides are usually mounted 8-12 inches from the water's surface based a several factors (turbidity of the water, depth of the tank, wattage of the fixture, specific needs of the photosynthetic organisms, etc.).  The best person to determine "how high" is you...after reading/researching the available material and learning about/understanding these factors.  If you haven't yet, please read here and among the associated links in blue...much, much more info to be found/absorbed than I can convey to you: http://wetwebmedia.com/marine/setup/lighting/fixtures.htm >>
Just a real quick side question, I Kinda wanted to get some torch coral but I read somewhere it can be very aggressive?
<<Indeed>>
Would I be able to keep Torch coral in a small tank with others?
<<If you can provide enough physical separation, yes.  Start with a small specimen and frag/trade/sell-off pieces as necessary to keep it small>>
Thank you,
Samantha
<<Quite welcome.  EricR>>

Lighting; MH and T5 - 02/07/2007
Hi Adam,
<Hey Gin Josh.>
Thank you for the fast response.
<We try our best.>
I probably would be looking at going for a shallow water bio-tope. If I went with the 175 or 250W pendant, how high above the tank should it be hung?
<Mmm...depending on how bad/good your heating problems are about 12"+...at least 8"...you don't want to cook your animals.>
I would be interested in the "more reputable models/brands out there" that you mentioned.
<Mmm...Sure I will list a few: Hamilton, Giesseman, PFO, Sunlight Supply (Just a personal plug I love the simplicity and effectiveness of the S.S. pendants)....>
Yes fluorescents would be tough on this but I may ask, What about T5/HO instead of metal halide?
<Ummm, I think they are different types of lighting for different types of applications but without going into too much detail...I am a huge fan of T-5's, great bulb life, very efficient when paired with the proper reflector.>
Thanks again.
<No prob.>
Josh Rosenberg
<Adam J.>

Tank Repair and Halide Question  2/5/07
Hello from Alabama,
   <Greetings from (today) sunny Southern California, though I will be literally next/next door in SC three days hence>
  Thank you for the great site and all of your help. I have two questions and will try to keep it brief. I have a small aquarium maintenance business
<Ahh, I did this for 19 years...>
and one of my customers has two marine aquariums, of which the questions are about. The first tank I have a question about is a 210 All-Glass reef-ready that when he had set-up (by someone else) the power compact strip light was laid directly on the glass lids causing both plastic braces to melt and break.
<Yes... not smart>
This of course has caused the front and back panels of glass to bow to a point where the braces have about a 1/2" gap where they used to meet.
<Uhh... I would fashion, re-install these braces... they are functional... not just for looks>
I'm not sure how long it has been like this, I have been servicing the tank for a couple of months and I feel like something should be done.
<I agree>
I know that the whole top trim can be removed and replaced with a new one, but I am a little scared to attempt this.
<Not that hard to do... Contact All-Glass re... they will instruct you, sell you the replacement bracing... You may well be able to "get away" with draining the tank only mostly...>
I was thinking about draining the tank down to a point where the tank receded to its normal width and the braces touched again,
and then attaching a new piece of 1/4" plexi-glass that would bridge over the broken brace and act as a new brace. I plan to attach this new piece by drilling holes and using plastic wing nuts. Of course I will have the PC on legs like it always should have been. Do you think this would be a worthwhile remedy for the problem?
<Mmm... I doubt if this repair would "hold" (just so much force), but worth attempting rather than doing nothing... If it were my account I'd effect the repair mentioned first>   
  My next question is concerning this same customer's second tank. It is a 135 gallon (72x18x24) acrylic tank. It has the standard acrylic top with two rectangular openings. We recently placed an HQI strip light that has 3-250 watt HQIs and 4-130 Actinic PCs. The two end HQI bulbs align over the openings in the top but about 80% of the center one is over the 7" acrylic  section between the two rectangles. I am currently not using the center light because I wasn't sure how hot it would get, fearing this tank would suffer like the above tank.
<You are wise here... I would NOT place a 250 watt HQI fixture here>
The bottom of the light fixture is about 5" off of the acrylic,
<Too close... I would have at a minimum a foot of space twixt the lamp and acrylic... Plexiglas has a surprisingly low flash point>
the top of the canopy is made with a plastic grid for ventilation, and the strip light has a cooling fan built in. The HQIs are on a timer and run about 9 hours a day. Based on this information do you think that it would be safe to use the center bulb?
   <I do NOT. Again, if the one fixture (or likely all) can be "lifted" the suggested height...>
  Thank you for your help, sorry I ran a little long.   
  Jeremy  <><
<No worries. Good to make your acquaintance. Bob Fenner>

MH Upgrade - 11/03/06
Dear Bob Fenner,
<<Eric Russell with you this morning>>
I've already read your info on lighting, but I am still a little confused.
<<Okay>>
Below is an email that I sent Current & Marine Depot, but I would like your opinion on the lighting upgrade and the exchange of bulbs.
<<Sure>>
My ceiling above the tank is 18 feet (slanted), so I "kind of" need to go with a fixture that sits on the tank or possibly a very nice wall mount.
<<I see...no wish to balance on a ladder eh?>>
Would I need a chiller, too?
<<That will remain to be seen...is not always a necessity based on your geographical location, ambient room temperature, tank location/configuration, etc...or can sometimes be replaced with fans mounted to blow across the surface of the water.  You will need to wait and see what impact the lighting has on your tank>>
>Dear Marine Depot & Current,
Awesome customer service replacing my 48" SunPod! Very quick response & just an overall excellent experience, especially since it was covered under the 1 year warranty, & no longer Marine Depot's responsibility! Over-the-top! Thanks!<
1) Since there are so many awesome reviews of bulbs out there, would it make sense to upgrade from the Current SunPod generic 14k bulb to say something like a Hamilton, XM, etc?
<<Doesn't make sense economically...unless the bulbs are unsuitable/very poor quality>>
Which one would you recommend if so!? (in the 10k to 14k range, i.e., white to blue)
<<Either the Hamilton or XM in 10K or 14K would likely be fine>>
2) Could you tell me what the final analysis was on the returned SunPod, so I know what to look for & do in the future?
3) My 55 gallon is only 20 inches deep, would it make any difference to upgrade from the 2x150 MH 48-inch SunPod to the new 2x250 MH?
<<Not necessary for this tank in my opinion>>
Also, my tank stays at 79 degrees with a fan on the sump.  Would the 2x250 cause my temp to go up too much?
<<With everything else remaining equal...probably not>>
Sincerely,
Ralph Scheriff
<<Regards, EricR>>
.........original email below:
the right MH lamp is much more blue & less intense
Dear Marine Depot,
Last December I purchased your SunPod light. Over the past 2 months the right MH lamp is much more blue & less intense than the left one. I replaced the bulbs last week, and the same thing is occurring on the same sides. Although they are much brighter with the new bulbs, the right side is still much more blue than the left and less intense. Would that be an electronic or ballast issue?
Sincerely,
Ralph Scheriff

Re: MH Upgrade - 11/05/06
Dear Eric,
<<Hello Ralph!>>
Thank you for your information!
<<My pleasure to provide>>
One last question, however; how many hours of MH light time each day considering I have SPS, Clams, etc. in that 55 gallon, 20 inch deep tank with 2 x 150 HQI?
<<Something in the 12-14 hour range (I run my halides with a 13-hour “on” cycle)>>
Sincerely,
Ralph
<<Regards, EricR>>

Metal Halide Voltage Question   10/11/06
Hey Everyone,
<Hello Matt>
Although I browse your site quite frequently, I've usually found what I was looking for.  I think I may have missed it in this case, but I'm curious. I've been an employee and a manager of my LFS for quite some time, only recently ending my employment to finish college.  I have learned a great deal about this hobby, and usually find myself giving advice to other people.  I need the expert help in this case.  Over the years, I have installed many metal halide systems and never gave it a passing thought. Until recently, when a friend of mind an aquarium metal halide catch fire. Luckily, there was only superficial damage, and nothing appears to be hurt in the aquarium, but it definitely could have been a nightmare.  So the question I have, as I investigate this, is.. what is the output voltage and starting voltage for a metal halide  (400W, 14000K, Mogul w/ electronic ballast)?  I know the input voltage is 115V, standard household, but what I can't seem to find anywhere, is what the operating voltage is.  I don't need an exact, but it has to be more than 115V, otherwise a ballast wouldn't be necessary.
<On a Venture, pulse start, 175 watt ballast, the typical open circuit voltage reading would be between 240 and 290 volts, with nominal at 265 volts.  It is highly recommended to use a GFCI with these systems.  For that matter, with any aquarium lighting application.>
Thanks, in advance, for your help.
<You're welcome.  James (Salty Dog)>
Matt

Remote Metal Halide Ballast  - 10/08/06
Good day my fellow afishianados!
<And to you also.>
I have a quick question for you.
Is it OK to remote a MH Ballast to the attic?
<Depends on the ballast.>
I bought a used setup a while back and it came with (3) 175 W MH bulbs and a monster home made ballast. It is encased in a silver aluminum box and gets a bit warm (as I'm sure you can imagine.)
I had it set outside the stand all summer and my water temp stayed at 79 DEG. But I recently brought home a new puppy so had to move it back under the stand. Now my tank temp rises to 83 DEG during the day then back to 80 ish at night. This is on a 210 GAL Display with 300 GAL sump and fuge in the basement. Not only do I not like the temp swings, but the AC stays on all day and night and it's in the 50's outside around here...
Anyway, I considered moving it to the basement, but the wires aren't really long enough to accomplish this.  So, I was thinking about remoting it to the attic where the heat wouldn't be a factor at all but am wondering about the climate up there.
It is an older house with the Louvers on the ends of the attic for air circulation. They do not let any water in but what about when it gets foggy? Also, will the high temps in the summer and the low temps in the winter have any effect on the ballast itself?
<Should not, the caps in these ballasts are rated at a 200C operating temperature.>
It will be positioned about 40' from either end of the attic in the center of the house.
<My concern here is whether the ballasts are a pulse start type.  If they are, the igniter cannot be more than 3 feet from the lamp.  A #12 high voltage cord will be needed for each lamp, in the 40 foot run you mentioned.  Care must be taken here in your application, as an incorrect application for the ballasts you are using, could result in a fire.>
As always, I truly appreciate all that you fine folks do for the hobby and hope to meet you all and be able to contribute one day.
<Thank you, James (Salty Dog)>
Tom (The Tool Man)

Metal Halide Bulb Placement (Parallel? or Perpendicular?) - 04/30/06
Hello wet web,
<<Hiya Mike!>>
Let me lay out what system I have really quick to give you a better idea of what we are working with.
<<Thank you>>
I have a 100 gallon SeaClear System-II aquarium.  One main pump, two powerheads and a separate pump for the chiller.  2x175watt MH and a 1/4 JBJ Arctica chiller.  I have read through your FAQ's but have not gotten a definite answer.
<<Ok>>
My question is, is a 2-degree temperature fluctuation too much for my fish and coral?
<<Not usually, no>>
The chiller cools from 78.5 to 76.5 in about 20-25min and it will do this about 2-3 times per day depending on how hot the day is.
<<Mmm...that's a pretty rapid drop>>
Is this how this chiller is supposed to work?
<<Yep>>
If not, what is an acceptable range for a chiller to chill?
<<?>>
Do I have the settings on wrong?
<<Not "wrong" per se, but could be "improved".  Does your chiller allow you to adjust the temperature differential?  You should be able to set the differential (the number of "degrees" the water temp is allowed to rise from your "set" temperature before the chiller kicks on), adjust this to 1-degree of differential to reduce the size of the temperature drop>>
I have the low setting at 76.5 and the high setting at 78.5 degrees.
<<Ahh!>>
What am I doing wrong?
<<Nothing really, all is probably fine unless you are seeing signs of stress in your tank inhabitants.  But for a more "stable" environment, you can either increase your "low" setting or decrease your "high" setting>>
Also, does it matter if I mount my Halides perpendicular or parallel to the front of my tank?
<<Most folks opt for "parallel", but if you have adequate light spread/coverage I don't see what difference it really makes>>
Keep in mind that I have a rectangular 5' acrylic tank.
<<I too have an acrylic tank...my halides are mounted parallel>>
I was thinking of using the PFO parallel reflector that can
also hold two power compacts or I can also use the PFO parabolic reflector which places the bulbs perpendicular to the front of the tank.  Do you guys know if these reflectors are any good?
<<I use PFO reflectors, I think they are a fine product/value>>
The reason I'm asking is because I heard that if you place Halides perpendicular to the front of a tank it can warp the front of it.
<<Huh?! How?>>
Is this true?
<<Not that I've ever heard>>
What can happen to my tank?
<<Whether your bulbs are positioned parallel or perpendicular should make no difference in this respect>>
The help is much appreciated,
Mike
<<Mike, considering the dimensions of your tank I think a parallel configuration would be optimal...but if you' rather go perpendicular I don't see any great problems with this either.  Regards, Eric Russell>>

Lighting/Reef/MH lighting choice for 36x24x24 tank  - 5/2/2006
Hey Crew,
<Hey Jimbo>
Setting up my first reef tank, it is 36x24x24, and have fallen in love with MH. <Love em to death!> It will be a mixed garden but I envision a couple of easier SPS, such as Montipora and a lower light clam such as Deresa one day. If I do a frag or two of Acro it will be fine to keep it up high. Struggling with the lighting choice, I have a hood with 11" to the water, will use a couple of fans. All of the options below use a couple T5 Actinics as well as the MH.
1. Dual 175 moguls using PFO Optimal perpendicular reflector. Icecap ballast and XM 10k's. These are the retro reflectors and would be run with no glass shield.
2. Dual 150 DE's using ROIII pendants, Icecap ballast and AB 10k's.
3. A single 250w DE in the fancy new Sunlight Supply Lumenmax 3 pendant, which is supposed to give 2x2 coverage at 9" and less of the spotlight effect of other DE pendants. I don't mind the lack of coverage on the edges.
<For your 24" deep tank, and the inverts you want to keep, I like option number three the best.  Do go with a HQI, much more compact.>
Or if you have a better idea lay it on me!
Thanks so much,
<You're welcome James.  Why do I like that name?  James (Salty Dog)>
James

Re: Reef Lighting    5/2/06
Salty Dog,
<Scott>
I have existing ballasts for MHs that I used previously.  Do HQI fixtures require different ballasts than standard MHs?
<Yes.>  Would your recommendation be just to incorporate the HQIs into a hood or is there any benefit to one of the existing fixtures that you can suspend above the tank?
<I'd opt for a on-tank fixture or incorporate into a hood.  The hanging fixtures will light up the room pretty well so if the tank is in a TV room you will probably see plenty of glare on the screen.  On-tank fixtures will also provide more light per watt as it is directed right into the tank.  James (Salty Dog)>
Scott

Lighting Question... extending wiring on/for MHs (Salty!)  7/14/06
Good day fine people!  
<And to you>
Once again I turn to you for a little expertise that I seem to be lacking.
I am in the setup phase of my 200 GAL tank with 300 GAL fuge/sump/return in the basement and have a quick question.
<Hotay!>
I want to remote my magnetic ballast for the 3x 175 W MH lights to the basement. I am thinking that if I cut the existing cable between the ballast and the lights and splice some 3 wire Romex cable in, there shouldn't be any problems, but just wanted to run it by you fine folks to make sure I am not missing something. If it matters, it will be about 30' from the ballast to the lights.
<Mmm... am going to send this response to our resident "electrician", Salty/JamesG... If it were me, mine, I would NOT do this, but instead contact the actual manufacturer, ask for their input, and if they're amenable, buy new cable from them... follow their directions re re-terminating the connections...>
Thanks for your time and all you do for our hobby (sickness ;-)  )
<Mmmm... Well... do perhaps wait on Salty's go here as well... I'm just too concerned re the gauge of wire over the run here, the implications of overheating, possible fire and electrical shock hazard. Bob Fenner>

Re: Lighting Question... extending wiring on/for MHs (Salty!)  7/15/06
Good day fine people!  
<And to you>
Once again I turn to you for a little expertise that I seem to be lacking.
I am in the setup phase of my 200 GAL tank with 300 GAL fuge/sump/return in the basement and have a quick question.
<Hotay!>
I want to remote my magnetic ballast for the 3x 175 W MH lights to the basement. I am thinking that if I cut the existing cable between the ballast and the lights and splice some 3 wire Romex cable in, there shouldn't be any problems, but just wanted to run it by you fine folks to make sure I am not missing something. If it matters, it will be about 30' from the ballast to the lights.
<Mmm... am going to send this response to our resident "electrician", Salty/JamesG... If it were me, mine, I would NOT do this, but instead contact the actual manufacturer, ask for their input, and if they're amenable, buy new cable from them... follow their directions re re-terminating the connections...>
Thanks for your time and all you do for our hobby (sickness ;-)  )
<Mmmm... Well... do perhaps wait on Salty's go here as well... I'm just too concerned re the gauge of wire over the run here, the implications of overheating, possible fire and electrical shock hazard. Bob Fenner>
<<Extending the wire length is not recommended, but not for overheating, as this can be overcome by using a larger gauge wire.  The problem we have here is the extremely high starting voltage of the lamps, some as much as 4000 volts (low current).  Extending the length of wire 30 feet (with standard #14 Romex) will more than likely cause a voltage drop in start-up which will lead to shortened bulb life due to longer start times, if the lamp even starts at all. This will all depend on the VA capacity of the start circuit transformer being used in the ballast.  Romex is definitely a no-no as the insulation on this wire is not rated for that kind of starting voltage, and leakage can/will occur and could lead to electrical shock.  I ditto Bob's suggestion of contacting the manufacturer re this before doing, and get information on proper wire size and type, warranty considerations, feasibility of doing such, etc.  James (Salty Dog)>>
<Thanks for this Big J! BobF>

Matching MH Bulbs to Ballasts - 07/21/06
I bought 2 175W HQI DE 20k MH bulbs on eBay for $20 in a bulk box of mixed type MH bulbs.  
<<175W double-end (DE) bulbs?  Are you sure?  I didn't think there was such a bulb...nor does a quick Google search find one...curious>>
My questions:
1.)  Can I run them on the same ballast as the 175w SE bulbs or will I have to upgrade to different ballast.  One of my ballast is the Advance F-can (72C5581 N-P) ballast.
<<I believe this is 150W ballast, is it not?  It will not run the 175W bulbs...DE or otherwise>>
The other is DIY Advance ballast.
<<Mmm, this tells me nothing...>>  
2.)  Should I upgrade to one of the HQI ballast or just plug and play?
<<If that is a possibility, then yes.  My favorites are the IceCap electronic ballasts.  Great product/customer service/warranty...in my opinion of course>>
3.)  Will a 150w HQI <<bulb>> be able to run on these type of ballast also?
<<Are we talking about the F-can ballast again?  Maybe, though I think unlikely unless that model was specifically designed for such a bulb>>
Thanks,
Shaun Montgomery
<<Regards, Eric Russell>>

Re: Matching MH Bulbs to Ballasts II - 07/21/06
Yes there are a couple of 175 DE bulbs on the market.  Aquatrade sells them with their MH fixtures here: http://www.aquatraders.com/index.asp?PageAction=VIEWCATS
<http://www.aquatraders.com/index.asp?PageAction=VIEWCATS&Category=49>
&Category=49
http://www.aquatraders.com/index.asp?PageAction=VIEWCATS
<http://www.aquatraders.com/index.asp?PageAction=VIEWCATS&Category=24>
&Category=24
<http://www.aquatraders.com/index.asp?PageAction=VIEWCATS&Category=49>
<<Mmm, yes...have seen these (advertised) before now that you mention...>>
Also what is the bulb type of 175 DE and 150 DE bulbs.  (EX. 175 SE are M57)
<<Don't know/am aware the DE bulbs have a "type"...perhaps if you contact the manufacturer re...>>
Can I build a DIY house for the double ended bulbs and just buy the UV glass?
<<Sure>>
Or do I have to buy the full reflector.
<<Nope, you can find/buy the UV glass online.  Some brand names are Optivex, UVILEX 390, and OptiClear...likely others can be found with a Google search re "UV Filter Glass">>
Thanks,
Shaun Montgomery
<<Regards, EricR>>

Mercury Vapor Ballast Question   8/14/06
Ok I've been doing a lot of diy reading and can't seem to find a good answer to my question.
I would like to have 2 MH of some type to go along with my 4 VHO's on my 55gal tank but have a small problem don't have the cash flow that some
of the people in this hobby have. So I've been researching diy MH. I've found a few people speak of using a out door mercury vapor light that
cost around 40 bucks not using the bulb that comes with it and using a 250w 65k Iwasakis bulb. Now how true is this? Can it be done? If this
works I can just put 1 or 2 more actinic bulbs on my VHO set up to off set the color. Some help anyone, or a little insight to this please. I value your opinion always.
<Some mercury vapor ballasts can run both, mercury vapor and metal halide bulbs.  You must be sure that the ballast itself is labeled,
"For H39 or M59 bulbs".  These numbers are just an example, they will differ depending on the wattage of the fixture.  It is very unlikely that
the 40 dollar outside mercury vapor fixture is going to have this type of ballast.  I would not recommend using a MH bulb with a "H" only type ballast.  
James (Salty Dog)>
Dez

Lighting Confusion  9/9/06
Dear Bob et al.,
<Jim>
I have read most of the articles on WWM media re: lighting many times over the years, and have appreciated the improved understanding I have gained.  But I am increasingly one thing.  Bob, in your article Marine Lighting: Quality, Quantity and Duration, you encourage the use of fluorescents, even normal output fluorescents, in reefkeeping.
<Mmm, yes... in part these are "old" (more than a decade) statements/articles... and in part I am a big/ger fan of this technology for most folks... as we'll discuss further here>
  You list HO, VHO and PC as higher cost, and in some ways less desirable solutions, and you put MH's under the category of 'losing' technologies, because of their high cost, the massive heat problems, and the fact that they are actually too intense for many life forms.
<Mmmm... thank you for this... opportunity, prompting... I would not label MH as "losing technology" per se... but inferior for many settings (tanks shallower than a foot and a half in actual water depth, most organism mixes... but/and most importantly ones/systems that don't have matched capacities for providing adequate biomineral, other rate-limiting aspects... boosted light/intensity alone is not a panacea>
Based on this and much other reading and input, I chose to go with 4x110W VHO's for my 72G reef, which by your article exceeds the 1-2w/gallon you recommend, and it has worked great for the few soft corals and several LPS corals I have kept: Euphyllids, Caulastrea, Turbinaria, Favites, Trachyphyllia, and Lobophyllia (not sure I spelled those right).
<Close enough. Will fix before posting>
In fact, I had to move the Favites DOWN after it started to bleach and pull in when I put it high on the rock wall.  Last year, I wanted to purchase a crocea clam, but was angrily told by several reefkeepers I would just be killing a helpless animal by trying to keep it under these woefully inadequate lighting conditions.  I wrote in to WWM, and was reassuringly told "not to believe the hype" and that, given the correct water parameters, a crocea could live quite happily under VHO's, if kept within one foot of the surface.  My first clam died shortly after purchase (too quickly to be lighting, I believe) but my second crocea has been alive and doing well for six months.  It has grown, albeit slowly, putting on about a quarter inch of new shell in those 6 months.  Okay, now to the question:
My 72G reef recently blew out a seam, and I am quickly upgrading to a 150XH.  I chose the 150XH, despite the fact that some have expressed concern about the undesirability of deep reef tanks, for two reasons: space limitations within the house (six feet long just won't fit), and the fact that my lighting is all set up for a four foot tank.  But the concern has been raised that my 440W of VHO will truly not get the job done on a tank that deep.  So I started reading again, and I noticed that, despite everything your article said about MH being a 'losing' technology, you seem to recommend them fairly often in your FAQ's.  For example, a recent post:
Dear Bob,
My present tank is 60"L x 24" W x 30" H housing only softies due to angels and BF's lit by 6 x 40W NO fluorescents.
<Okay>
I have two options of light upgrade, 2 x 150W MH or 8 x 55W PC. Taking into consideration that I do not plan to have SPS, which would be a better option.
<A tough one here... both could be made to work. I will opt for the metal halides here though... due to the size, shape of tank, my personal "looks" preferences. Will be spectacular. Bob Fenner>
Regards.
This seems like a complete turnaround from your earlier position!
<Mmm... perhaps... is mostly a change due to tank sizes (getting larger, deeper) and improved "other" technology, and its popularity>
(I am not trying to be accusatory, I am trying to understand.)  Is this recommendation because of the deeper than "normal" tank listed by the author of the question, or has you opinion on the usefulness/value of MH changed considerably since you wrote the article I mentioned, or is there some other consideration I am missing?
<Is mostly the former, a bit the latter>
  I have zero desire to spend lots of unnecessary money on lighting, or worse yet, a chiller.  But I also don't want to do my animals a disservice.  I don't mind relatively slow growth (in fact, I prefer it.  I have had to frag my Euphylliids and sell/trade the pieces about eight times in the last four years because they got too big and started stinging each other, and that was only under VHO's).  But I don't want to starve them for light.
<Mmm, let me try to make a point this way. Your Euphylliids are receiving much more photonic energy than they would in the wild... can/could be metabolically boosted further still with more light and concurrent other conditions... is this "worth it?"... to frag more often? The added risk should the power fail once your animals are "boosted lighting" photo-adapted, the cost of energy consumption? Not an easy "yes/no" question...>
In my new 150XH, I am willing to keep most of the corals relatively higher up on the rock structure, though a few, like my very large (8-9" dia), seven year old bright pink rose Trach will still need to go on the bottom.  I have no intention of beginning to keep SPS anytime soon.  Will the VHO's serve?
<Could... but to proffer a more "complete" response, if this were your starting tank, and you were/are of the apparent level of sophistication as you appear... I would likely start with MH... two 250w pendants likely>
Would they serve if I added a few more VHO's/PC's?  Or, given the depth of the tank, had I better consider MH's?
<This last>
If so, what wattage?  I am really not excited about the idea of two 400W MH's in my living room.
<Me neither... would need a chiller and a basket of sunglasses to issue to visitors and family>
Would two 150W DE's fit the bill, or do I need to go with 250W's?  A little clarification please!
<The 150's would "get you" about what your present fluorescents do (though look a bit nicer)... IF you're switching to MH... I'd go with two 250's>
Very confused, but sincerely grateful for your help,
Jim Jensen
<Thank you for the opportunity to make myself clearer. BobF, visiting in Jamaica>

PC or MH? - 09/05/06
Hi,
<<Hello>>
I am confused about what type of lighting system I should go with.
<<Whichever best suits the species of animals you plan to keep>>
I have looked around your site and I'm still a little confused...
<<Did you look here? http://www.wetwebmedia.com/marlgtganthony.htm    and here? http://www.wetwebmedia.com/marine/setup/lighting/index.htm >>
  I plan on having soft coral in my 75, tree corals, and some zoos and possibly a brain coral....  I'm not entirely sure if I should go with power compact or metal halide with VHO... Thanks.
Adam
<<Either choice will suffice.  The power compacts would likely be cheaper to purchase, but the metal halides give more bang for the buck in my opinion.  A pair of 150w or 175w MH fixtures with bulbs in the 10000K-14000k range should do nicely.  EricR>>

Re: PC or MH? - 09/07/06
Thank you for your advice...
<<My pleasure to share>>
I have one last question...  If I went with 2 150w HQI bulbs at the 14k range, would I be able to leave those on for 8 hrs?
<<Mmm, I recommend you leave them on for 12-13 hours per day as this more closely replicates the daytime photo-period in the tropics where your tank inhabitants are/will be collected>>
Thanks again,
Adam Dusza
<<Always happy to assist.  Eric Russell>>

Which Lighting Solution? - 09/14/06
If I were to make another investment in this tank should I invest in power compacts, T5's or another type of halide.
<<I prefer metal halide lighting for most any/all marine systems.  Is a great look, and can usually be positioned/Kelvin temperature adjusted to suit most any biotope>>
There are two anemones, the original one split, all others are soft corals like mushroom' and leathers.
<<Firstly, this is an unnatural mix, thus making it difficult to provide suitable lighting.  But with the presence of the anemones...metal halide lighting most definitely, in my opinion>>
The fish include two perculas and a golden angel.  Cost to run and purchase is a concern, Thanks Ron.
<<Doesn't cost any more to run 300 watts of metal halide lighting than it does to run 300 watts of fluorescent lighting...and the metal halide bulbs have a longer useful lifespan.  Regards, EricR>>

Re: Which Lighting Solution? - 09/15/06
So would another Coralife 150 watt tank-mount be a good investment to supplement the one that I already have?
<<If you're happy with it...sure.  EricR>>

Metal Halide Lighting And Acrylic Tanks - 11/27/05
Hi,
<<Hello>>
I've searched and researched my question, but have come across no answer so I wanted to run it by you.
<<Alrighty>>
I have a 75 gallon pentagon acrylic tank. I am considering purchasing the Aqualight Pro with the 150 watt metal halide and 2X65 watt actinics. My tank has a closed top with a removable acrylic piece that covers it.
<<Typical>>
Using the mounting legs, would I have to worry about the heat melting the top of my tank? That may be a stupid question, but I'm new to metal halide lighting and can't find anything to answer this.
<<Not a stupid question. Keep the bulb height 6"-8" above the tank and you'll be fine. I would also remove the "removable" piece to aid with light penetration/gas exchange.>>
Thanks for your time.
Brian
<<Welcome, EricR>>

Metal Halides And Lens Covers - 11/27/05
Hey crew!
<<Hey Jenn!>>
Thanks for all of your great info!
<<You're welcome>>
Quick question: currently running 50 gal reef tank with 400w 20K bulb and it hangs about 8" from the water's surface (We love SPS).
<<Yowza...a lot of light!>>
There is no cover on the tank, but could we take the glass cover off of the halide fixture in order to let more light get to the tank?
<<If this is a single-end bulb (Mogul) fixture, yes...if a double-end bulb (typically referred to as HQI) fixture, no...>>
Would it be dangerous?
<<It is generally accepted that the Mogul style bulbs provide enough UV protection with the outer glass envelope that is an integral part of the bulb. It is also generally accepted that HQI style bulbs need the glass (or plastic) lens of the fixture to provide the necessary UV protection. I run Mogul style bulbs and I "don't" use any type of lens/cover.>>
We noticed that a few LFS's do that. We have found that when we bring SPS home, they lose some color compared to what they had in the store.
<<Mmm...coral pigmentation/color is not always about light, though if it were me I would change that 20000K bulb out for one of 10000K. Other things to consider to help with coral color are water quality (use of carbon, ozone, skimming), water flow/movement, and coral feeding.>>
Thank you!
Jenn
<<Welcome, EricR>><RMF is concerned with the possibility of splashing water, burned elbows...>

Metal Halide Lighting, Fixture Manufacturer Contact Information, Kudos  11/30/05
Crew- 
<Craig>
I just wanted to pass along some contact info to our fellow reef keepers.  There is a manufacturer located in Indianapolis, Indiana who builds metal halide setups with remote ballasts at extremely competitive prices. I do not work for him, I just found him on eBay. I was a bit skeptical as to how quality his products were (especially at the prices being asked) but since I live in the area, I visited his facilities in person. 
About six months ago, I bought both metal halide units that were 400W w/ a 20K bulb and 250W w/ a 10K bulb. The 400W ran me $110 and the 275W was $90. Both units came with a 2 year warranty. His prices are absurdly low, but the units are quality, and I would recommend them to others. He does charge for shipping (don't know the rates). He prefers PayPal for payments, I am not sure if other payment methods are offered.
These units have done very well for me, and since this hobby tends to break your wallet, I just thought I would pass the info along. I am not one for hawking products for anyone (or for any reason, really), but he has been a solid guy in his dealings with me and others in the area. He has been in the business for five years, and I told him I would refer him to others since he has only recently expanded his business from horticulture to marine applications.
His contact info:
Michael Hurrle
Indoor Sun (Indianapolis, Indiana)
M3i6k0e@aol.com 
317.345.1369
If you can, please post this info for others to use. Thanks! Craig 
<<Done!  Marina>>
<Thanks for sharing, Craig. I'm sure this will be posted on the daily FAQ's. James (Salty Dog)>

Metal Halide Suspension height  12/5/05
Hello all,
<Hi Paul.>
Thanks so much for all of the support, I have a question.
<You are welcome and sure.>
I have recently upgraded my lighting system, I had 220 watts pc w/ flo actinics. Well my tank is your normal run of the mill 90 gallon, 4 ft. long and 24' tall by 18" deep.  Well I have recently acquired a HQI retrofit kit: dual 250 watts with 14000k bulbs (real pretty with a hint of blue)
<Yes I admit the 14000K and 20000K bulbs are aesthetically appealing but in all honesty your photosynthetic animals will prefer lights in the 6500K to 10000K range.>
so I rebuilt a new canopy (a lot taller) than the original; this sets the HQI bulbs exactly 9 inches from the surface of the water (from the protective U.V. glass to the water surface) I have slowly introduced these new lights over a period of about three and a half weeks increasing light exposure daily. Everything looks o.k. so far.
<Sounds good.>
I turn on my pc 96 watt 50/50 first thing in the morning for about a n hour and then introduce the HQIs (then turn off the pc's) I run the HQIs for about 8 hours and then turn them off and run my pc's again for a 2 hour period (trying to
simulate the course of a day).
<Right.>
I currently have:
150 lbs. live assorted rock
pulsing xenias
1 leather toadstool
1 open brain coral
6 green Ricordea mushrooms
flower pot (Goniopora
<Goniopora, a notoriously short lived animal in captivity.>
(sorry about spelling)
<No worries.>
button polyps
1, yellow tang,
2 percula,
1, 6 line wrasse,
2, green Chromis,
1 dragonet mandarin,
<I hope you are aware of the needs of this animal, it’s in direct competition with the six line wrasse for its food source…they aren’t the best tank mates to say the least.>
1 brittle star, and clean up crew.
Should I modify my canopy to bring the lighting even farther away? I know I should be 8-12 inches or so according to the board but my tank is shallow for a total of 500 watts of HQI.
<You can get away with 9” in this case, as long as the temperature is under control and everything is well ventilated. This is a lot of light for the animals you have but it will also allow you to attempt more light demanding species in the future.>
How high would you recommend I bring the lights from the surface of the water.
<At least 8”, which you have done.>
Oh yeah...by the way the back of the canopy is fully open and I run one small pc fan in the back it seems to keep the wood canopy slightly warm to the touch and the water temp a constant 79 degrees.
<Yes these lights are very hot, as I’m sure you know. There will always be some detectable heat with this set-up (I’ve burned myself on mine quite a few times…and been shocked by them, long story, anyway just be careful) as long your temperature is stable and there is no “over” heating where it becomes dangerous (for you), this is fine.>
thank you for any help in advance.
<Welcome.>
Paul
<Adam J.>

HQI lighting units  12/10/05
Hello Wet Web Guys & Gals;
<Hi John.>
<<A gal waves.>>
I currently am planning my next reef aquarium. 
<Ooh, fun.>
I will be upgrading from my four foot 90 gallon tank (by nature of it's/my evolution, is a bit of a garden reef) to a six foot x 18 inch tank (I would prefer a 24" wide tank, but it would be too tight in our living room) which will be either 24 or 29 inches tall. 
<24'd will be easier to clean and light.>
As a consequence of this, I am looking into lighting systems. I have looked at the various tanks featured in Michael Paletta's "Ultimate Marine Aquariums", and it seems that the popular way of lighting a six foot tank is with three 250 watt metal halides. Sensible enough. But, I may prefer to use a pre-built fixture such as Coralife's Aqualight Pro (rather than cobble up something myself), which comes with 3 x 150 watt HQI's for some reason.
<This is a pretty good fixture though there are a few other prefabricated units (which can also be ordered in the HQI format) made by other companies that I prefer, PFO and Hamilton to name a few.>
Now, I have perused the FAQ's as well as some other material, which leads me to believe that the lower power HQI's may be as bright as the higher power single-ended lamps.
<Possibly, if you compare a 150 watt HQI bulb and a 150 watt standard MH bulb (just the bulbs themselves) they are about even in terms of par production. However the small profile of the HQI bulbs allows them to be teamed up with much more efficient reflectors and thus an HQI bulb of lower wattage can match the output of a single ended bulb of higher wattage.>
Or, maybe not. It's a shame that these things are rated by watts rather than lumens!
<I agree.>
Anyway, do any of you have experience with this?
<Yes I use an HQI unit made by Hamilton and am very pleased with it.>
Can 450 watts of HQI effectively light a reef tank, with the ability to keep some Acroporas?
<The x3, 150 watt HQI would be fine for keeping most photosynthetic animals anywhere in your tank except possibly on the bottom you go with the 39\u201d height.>
Maybe some clams?
<Most clams will be fine with this lighting, squamosa and derasa in the sand, Croceas and maximas in the rockwork.>
It would be nice to get the equivalent of 750 watts of traditional MH lighting but only use 450 watts of power! 
<You can make this lighting work.>
Yours in Reefing;
<Good luck with the new set-up.>
John
<Adam J.>

Metal Halide Choices…I like HQI units  12/8/05
Hello,
<Hi James, this is Adam J helping you out tonight.>
First I really appreciate the service you provide.
<And I enjoy providing it.>
I have Mr. Calfo's Coral Propagation book on the way from Amazon as we speak.
<One of my favorites.>
Looked though the FAQ's and a couple came close, but no cigar. So....
<…here you are.>
Decided to jump into the reef world. I have an odd shaped tank, a 92 corner, that I am having trouble lighting, like lots of other people. I have built a nice custom hood that has 10" of clearance to the top of the tank. Being new I am going to try LPS and maybe a frag or two of SPS and I sure do think clam's are cool.
<Oh me too, Tridacnids are awesome.>
I have narrowed this down to two options. I under stand MH lights cover about a 2x2 window and my choices come down to space constraints.
<Okay.>
Option 1 is a single 250w mogul 10k retrofit style lamp in the middle of the canopy with (3) 1x55w PC's situated around the MH lamp.
<A good option, though I would rather have T-5 HO or VHO over the PC’s though as you mention space constraints may not permit this.>
Questions;
<Of course.>
Will this be bright enough on the edges of the 2x2 box the MH covers, there would be a good 16" on either side of this window of light.
<Obviously there would be some areas that receive more light than others. Though I don’t think you would end up with any “drastic” shadowed areas.>
Would this allow me to keep a clam on the sand bed and some light loving corals in the middle of the 2x2 window?
<Depends on the Clam, Squamosa and Derasas on the sand bed would be fine, Croceas and Maximas should probably be closer to the light in the rock work.>
Option 2 is two 150w HQI pendants along with a 1x96w PC in front and a 1x55w PC behind.
<I like that option a lot better. This would allow you to keep mostly any photosynthetic animals anywhere in the tank.>
Questions;
Where the two 2x2 windows of light overlap would this in effect be close to a 250w light?
<No it would be much more intense. 1, 150 watt HQI bulb has about the same par reading as the average 250 watt SE, mogul, bulb. The reflector and small profile of the HQI bulb allows for much more efficiency.>
For example where there is overlap would I be able to keep a clam down on the sand bed?
<See above.>
Also could I keep any corals down on the sand bed where there is only single coverage of one of the 150w HQI's?
<Yes the as long its not a brightly colored (ultra light demanding) SPS such as an Acropora most should be just fine, especially the LPS you mentioned.>
Final question, which one do you recommend?
<I immensely prefer your second option of the duel HQI units.>
Thanks so much!
<You are quite welcome.>
James
<Adam J.> 

General Lighting Questions 1/23/06 HQI
Hello, First thanks for being there to answer all of our questions, you folks are really appreciated out in the trenches.
<Glad to be of service!>
When we say to mount MH lights 8-12" above the water, does that mean the bulb or the bottom of the fixture? These would be HQI pendants in particular.
<Generally, most people understand this to mean the distance from the lamp.>
Also would you be willing to take a crack at this question (22" depth of water)....a 150 watt HQI mounted with the bottom of the reflector at 8" from the water is roughly equivalent intensity wise to a 250 watt HQI mounted at what distance above the water?
<Hmmm... too many variables, but not more than about two inches, assuming that the same reflector is being used.  Not only is the distance itself a factor, but the spread of the reflector will come into play.  A light meter would be really handy for this determination.  Best Regards.  AdamC.>

MH lighting...  - 2/15/2006
Hello James,
Thanks for your feedback. <You're welcome.> I have a follow up question regarding the lighting.  The 250w HQI idea sounds good but I've read on wetwebmedia that some corals will not thrive under the intensity of 250w halides. <Yes, but not the corals you have in mind. The orange cup coral is one such coral that requires low lighting.> Do you see this as being a problem based on the corals I mentioned in my previous e-mail? <The 250 watt light was a suggestion if you were interested in keeping clams, Acroporas, etc.  I've witnessed soft corals along with SPS/LPS doing extremely well under 400 watt halide systems.   James (Salty Dog)>
Best regards,
Kevin

Lighting question ... If James had to "put things away" or look for... would he make better, more accurate/complete titles? I think so
: SW invert. lighting, MH  2/13/06
When I setup my 150 acrylic (65x22x22) I had a FOWLR in mind.  My lighting consists of 4x65 pc (2@10k and 2 actinics) which suited me fine and my fish fine.  However, I have discovered the way cool world of inverts.  I now have a couple colonies of mushrooms and a colony of yellow polyps.  I would like to add more polyps, softies, and LPS, but I'm not sure I have enough light to meet the "moderate light" requirements of those animals.  I have a closed loop return on the top of the tank which prohibits me from adding any more fluorescents, so I was wondering if I should go with 2x150 or 2x175 MH?  I'm not really sure what "moderate light" means, but I do know that the same wattage of pc vs. MH is night and day.  My tank has three cut outs of equal size across the top, so I was thinking one pendant over each outside opening (which is where the bulk of my LR is) and leave the middle third to receive indirect light.  Ideally, I don't want to change anything, but I also want to ensure that my animals (present and future) have what they need to
thrive.  Your advice is greatly anticipated almost as much as it's valued. <Mike, your lighting level isn't really enough for the size tank you have unless you keep the colonies at the upper 1/3 level of the tank.  With the depth of your tank and the ability to place corals wherever in the tank, you should go with HQI's or halides.  Two 175 halides will let you keep soft corals and some LPS.  Do read here on lighting requirements for corals. http://www.wetwebmedia.com/corllgtg.htm  James (Salty Dog)>

Lighting/Invert/MH   2/14/06
Ames,
Thanks for the quick response. <You're welcome.> I figured what I currently have was a little on the wimpy side.  Will two 175 MH handle my situation, or would three be
better without being overkill? Or, would two or three 250 HQI lamps be an upgrade from the 175's or just a waste? Once the initial MH investment is
made the prices from two to three or 175 to 250 is not that big of a difference. I don't plan on supplementing with actinics, so would you
suggest something over 10K?  What would be the "best" configuration while still being reasonably responsible with my pennies? Again, you guys do a
great job!!! <If you go with the three 175's you should be able to keep most light loving inverts.  It would not be overkill by no means. If you would like to concentrate on SPS and clams then I would go with two 250's.  Personally, HQI is the way I'd go.  They offer a cleaner color spectrum, last longer and require less space. As for the K, I'd go with 12-14K lamps. James (Salty Dog)>

M57 ballast capacitor - 03/07/2006
Anyone on the crew know where a guy can score one or two capacitors for an m57 175w ballast?
I've searched high and low.  <Dan, I'm sure I can get these for you as I'm in the industrial controls business.  I do need info on the capacitor such as voltage, microfarad capacity, etc.  I can check on availability and price at that time.>
Help!
Thanks, <You're welcome.  James (Salty Dog)>
Daniel k. Babcock

Lighting/Inverts  - 03/12/2006
Hi, my name is Danny Richards <and mine is James, how are you?> and I had a question about metal halide lighting for my 150 gal aquarium. The tank is 60"L x 24"W x 25"T and I am trying  to decide if I should use 3 x 250 watt MHs or 2 x 400 watt MHs. And also if they should/need to be DEs or Mogul. Other than being single ended or double ended,  what is the difference between HQI and Mogul?? I am wanting to keep SPS and  Clams with very few fish. Also what Kelvin rating should I use? I like the way  14K and 20K look, but I have had people tell me those color temps. are not good  for SPS and Clams. Thank you for your time, and keep up the good work! <Danny, to the best of my knowledge all double ended lamps are of the HQI variety.  The mogul socket is for metal halide and these lamps cannot be swapped using the same ballast.  I think HQI is the best way to go.  A little more intensity watt for watt, more compact in size, and generally produce truer color temperatures.  Bulbs generally last a little longer also.  I think two 250 watt HQI's should be enough for your tank, and I'd probably go with something in the 12-14K in temperature.
James (Salty Dog)>                                                                              
Danny R.

MH Wiring Question  - 03/12/2006
Thanks for taking the time to answer questions, I have a canopy in my garage that is setup with 2 250 watt bulbs. I was wondering if it is possible to use one transformer to operate 2 lesser watt bulbs... I am building a canopy for a 55 gallon tank. How can I do this?  <Joe, you cannot do this, no mixing bulbs of different wattages.  Could start a fire here.  Local electrical distributors offer MH ballasts at reasonable prices, do check them out.  James (Salty Dog)>

Finding A Suitable MH Reflector - 04/11/06
It has been quite some time since I had to go to the all knowing WWM Crew with a question, but since this is a continual learning hobby, I have returned!
<<Indeed it is...for me as well...welcome back>>
I am rebuilding my 65g reef tank due to a forced relocation.  I have 4x 96w VHOs and 2x 250w MHs.  It isn't hard to fit all the lights in the canopy (19"x37"), but I had to seriously mangle the reflectors to put them in the first time.
<<I'll bet>>
Basically the MH's parabolic reflector had to be partially bent closed from their ~13" width to about 8" and I had to cut the VHOs' reflector in half to about 5" each because I have 2x VHOs on either side of the centered MHs.
<<Not so much an issue with the VHOs, but this would seriously affect your "spread" on the metal halides>>
I want to put a "less mangled" reflector in the hood this time. What do you think about a simple 36"x18"x2" reflector instead of the mix-match I have now? Do you know where I can get such a reflector?
<<Indeed I do!  PFO has a 36" parallel reflector with dual mogul sockets and "shelf" to mount your VHOs.  I have two of these over my 8ft tank.  Check out an example here:  http://oceanencounter.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=OE&Product_Code=P3PRW2MS&Category_Code=RSC  ...if you have any questions about the reflector, call Vince at Ocean Encounter...a very helpful individual>>
Thanks (again) for the help! -Jeff
<<Always a pleasure, EricR>>

Lighting hardware recommendations 10/28/04
Hello Sir Calfo,
<no need for the formality, my friend... certainly not "sir" - I work for a living <G>.>
I just had some quick questions about MH lighting.  Do you have a preferences between the PFO or Ice Cap digital ballasts?  
<I have no preference based on performance. At best... I lean towards Icecap based on a few studies/comparisons I've seen (see the coming article in Reefkeeping magazine... Nov. 04 I think... by Joe Burgher comparing ballasts and lamps. That all said, I do favor IceCap for their customer service which has been stellar from the very first day they hit the market>
I want to use a 400w 10,000k Ushio.  I've read that you can only use HQI bulbs with the PFO's??  The Ice Caps can take standard and HQI bulbs.  If the PFOs can take a standard bulb could you give me an opinion on which one works better?  
<I am not qualified/experienced with all new lamp combinations, alas. I will/would always defer to mfg rec's. >
I've very much so enjoyed your BOCP and Reef Inverts.  
<thanks kindly>
I'd like you know if you two are in the works for the next addition of the Natural Series?  
<why, yes... thanks for asking :) I am going over a final first pass of the bulk of content for the work... and it will be in the layout editors hands in days/weeks. Targeting a release of early next year for part 1 of 2 for the Reef Fishes volume>
I'll be looking forward to it if you guys are:)   Thanks a million
Chris AKA ~fishtank~
<looking forward to it too, my friend. Best regards, Anthony>

250 or 400 watt halides?
Gentlemen,
<< Kevin. >>
I have been reading all of the FAQs on your wonderful site, as well as reading quite a few books and I think I have gotten myself into a situation where I have too much information to make up my mind about a few things.
<< That is far better than having too little information. >>
My setup is as follows:
220 gallon tank (72x24x30)
Lighting is currently 3x250 20K Radium halides and 2x160 VHO Actinics
PH 8.2, SG 1.024, Temp 77-79, ALK 9.6 (Salifert), Calc 420 (Salifert), Ammonia/Nitrite/Nitrate/Phosphate all 0
I have 220 lbs Live Fiji rock that goes about halfway up the tank, but set in the middle of the tank to allow space behind for cleaning
Currently I have a number of SPS Frags (Acros & Montipora) and a colony of Pocillopora that I moved over from my 90 gallon tank
2 Euro-Reef ES 5-2 skimmers
Return pump pushes about 1500gph through 2 SeaSwirls, 3 Maxi jet powerheads, and 2 Seio?) 620 GPH powerheads for circulation.
Tank is about 8 months old (corals added about 2 months ago)
Lights about 6-7 inches off the water
Now to my questions:
1.  Everyone around here, including my LFS is telling me that I need to move up to 400W halides. << Before doing that, I'd probably move to 10k or 14k bulbs. >> I am seeing growth in 90% of my corals (One coral has grown about 1/2" and started three branches in the two months its been in the tank) and coloration is good (feed phytoplankton and zooplankton).  Because my rockwork only covers half of the tank I am concerned about putting corals near the bottom.  Also, would like to add clams at some time and am concerned for there well being. << Keep the clams up high. >> I don't mind investing to do this, but am not sure that I really need to. << I'm not sure if you need to either.  I think moving to a 10k bulb will do just as much good, coming from the 20k bulbs. >>  Mainly I am concerned about the long-term well being of my corals.  The more I read on the web the more conflicting information I get and can't make up my mind.  Any suggestions?
<< You can't have too much light.... but you may not need any more. >>
2.  Should I upgrade/add a new skimmer.  I am getting plenty of stinky results from my Euro-reefs, but their "rating" for tank size has seemed to drop since I bought them.
<< Well a bigger skimmer is always great.  But I'd check out lighting options over skimmer options first. >>
I appreciate your input.  
Thanks for your help in advance, Kevin Miklausich
Raleigh, NC
P.S. Sorry for the length of this email. << It's okay, we get lots of long emails. >>
<<  Blundell  >>
 

Halide UV shield
Hi guys, how goes the battle?
<< Very well. >>
I am up grading my lights from PCs to 2 X 250W 10,000K halides( still debating HQI or mogul), << HQI for sure. >> with 2 X 110 W VHO actinic.  It will be a retrofit  in a canopy, do I need any lens to protect my animals? << I think a piece of glass is a good idea.  Not necessary but a lot easier to clean than bulbs, and a good safety measure. >>
Thanks,
James
RI
<<  Blundell  >>

Metal Halides above water - 11/22/04
Hello, <Hey Brent!>
     I have a 55 gallon aquarium that I'd like to add metal halides.  Since my canopy is 7 inches, about 6 inches off of the surface of the water, it seems through reading the FAQs that I'll have to build a custom canopy.  Can you tell me how high the canopy should be?  <Well it is more important to note how high the recommendation for halides to be above the surface of the water. I would suggest 7-10 inches above the water (minimum) and definitely incorporate a fan or two into the canopy for cooling and moving the trapped heat out of the canopy. Do search the internet (via Google, Dogpile, or Yahoo) for DIY canopies. See if there are any helpful DIY plans available. Good luck ~Paul)
Thanks,
-Brent

UV filter?
Hi crew-
This is a second thought to my last question.  I am buying a DIY HQI  system.
They recommend (strongly) a UV filter.  What should I  use? << I use a 1.8" piece of glass.  I just bought regular glass at a glass store. >>
James
<<  Blundell  >>

Building your own metal halide system and canopy
Hi crew,
I hope all is well, and if its not, I hope it gets better.
I just finished building my own canopy to house my metal halide  system.  It is built out of pine.  My MH are complete DIY, with a  reflector.  Do 250 HQI's get hot enough to warrant some insulant between  the reflectors and the wood( I spent hours making it, don't want it to turn to  ashes just yet)? << I don't think so, but I would certainly have fans in there for water heat reasons, and I guess for wood heat reasons. >>
Is painting the inside of my canopy white sufficient to reflect  light? << No way!  For about $10 you can buy fantastic reflectors which make all the difference in the world.  Best money you will spend on your tank. >>
I also want to address everyone who asks a question to you guys.   There is a donation area to keep these guys up and running.  I figure about  1-2 dollars for every email you send to this site is more than worth it.   The information is invaluable, and it will keep them here.  I figure I have  asked about 10 questions this year, so I'll be sending them $20.  It is  expensive to run a site, so let's all chip in!!! << Well that is awful nice of you.  I think that is a little high, and I feel bad seeing you pay that much.  I think $.02 is fine (like asking for my two cents on something).  You know if you really want to, write in a question about advertising for a certain price (I have no idea how much) Cesnales will put an add for you on our site.  We appreciate the donations, and we are here to help. >>
Thank you crew.
James P
Rhode Island
<<  Blundell  >>

MH upgrade questions
Firstly let me thank you all for this invaluable and top notch resource! Always the first place I turn to for reef setup info. <Thanks, same here :)>
Three months ago,  I upgraded from a 30g oceanic "cube" to a 75g RR AGA with 20g sump and 10g gravity fed refugium.  <Neat, I love refugiums> Transferred livestock, now in new tank, consists of 2 Ocellaris, 1 RBTA, a few zoanthid colonies (I do not plan on keeping any LPS, SPS, or different anemones, by the way, in keeping with the needs of the RBTA.). I have a 4-5" DSB <excellent>  (so the water column effectively is only about 14-15" deep), and 75lbs of live rock/rubble.
The lighting system which was on the 30g, an Aqua Medic Aquaspacelight-mini 150w (with electronic ballast, and AB 10,000K DE bulb) is now illuminating one half of the new tank, where I have placed the zoanthids, and where the anemone has apparently agreed to stay put. <Unlike mine at the moment...> I plan on getting a second MH
pendant, and was considering an equivalent setup for the other half of the tank until I saw a friend's aquarium lit with AB 20K DE bulbs--and absolutely loved it.  <About to get a 20k bulb for my halide...PC fixtures are annoying> I am concerned however that the lower light
output of the 20K bulbs would slow down zoanthid growth. Would it be advisable, with 20K bulbs, to get a 250w pendant for one side of the tank, even if that meant slightly uneven illumination, to make up for the lower light.  <Just how fast do you want those zoanthids to grow?  As always, the farther away from 5500-6500k the slower growth you'll see, but I doubt it would be more than barely noticeable in a hobbyist setup.  Zoanthid growth is more inclined to change between species more than anything: I wouldn't worry about it> I would have the whole tank be lit by AB 20K bulbs, starting out small colonies under the 250w for accelerated growth. Is it safe/recommendable with
15" water depth. <Not needed with your water depth\stock, but entirely doable...consider some maximas\Croceas while you're at it ;)  Mount the lights ~10-12" above the surface, to avoid shock\overheating> How would the RBTA likely handle the
shift in color temp and intensity? <Shift shouldn't be much of a problem, but make use of the screen method to acclimate to the intensity>
The other concern for me is electrical cost-- I live in California. I plan on getting an electronic ballast, either way, so as to cut down on the heat which tends to be a problem in my small fish room. I am currently looking at the Geissmann Nova pendant, with its remote ballast (the electronic ballast on the Aqua Medic has been giving me problems--I'm hoping that having a remote ballast away from the heat of the bulb will ultimately prove a better choice).  <No personal experience with that fixture> Would
150w MH + 250w MH represent a significantly bigger power expenditure than, say, 2 150w MH with 2 65w PC actinic supplementation? 400w MH  vs.  300w MH + 130 w PC ? -- all this assuming that the 250w is even
safe/feasible.  <Seeing as amps=watts\voltage, you will be using less amperage with your new setup, thus saving you in kilowatt hours, at least a little bit.  The 250 watt setup sounds fine if that's what you want to do, but if you don't plan on adding clams\SPS, might as well use 175's or 150's in ~15" of water>
Any input and suggestions greatly appreciated, <Anytime>
Al
<M.Maddox>

Mixing MH Wattages
Hi,
I have 3x175W (6500K) + 2x140W VHO (1 super actinic R, 1 actinic white). I'm considering upgrading the middle MH bulb/ballast to 400W.  Is that a bad idea to mix different wattage metal halide bulbs? I have a 6' 150 with 'usable' dimensions of about 72L x 24H x 18W. Also I currently have glass covers on top of 2/3 sections of the tank (just
sitting on the braces). I did that to reduce splash onto the halides in the canopy but now those glass tops are getting covered in salt. Is there a material that will not accumulate salt and will let most light pass through them?
Thanks!!
<Hello, I don't see a problem mixing the two different wattages except that the corals might be shocked.  I would put the higher light corals in the middle section where the 400W metal halides are going to be.  The best thing you can do about your lids is to clean them weekly.  Good Luck. MikeB.>

MH Lighting
Hi, I'm planning a lighting system for a 215 gal reef rank. I want to keep some SPS corals, clams, and some softies--a full blown reef tank.
I have a PC fixture that will produce about 200 W of actinic light. I'm thinking that I will need about 800 more watts of light.<your figures are correct.> At this point, I think that two 400 W MH lights would be the best way to fill that gap. Please say if any of that sounds like a bad idea.<I would go with three 250's> Since it's a pretty large scale lighting system, I'm obviously looking for ways to cut costs. I'm somewhat handy, so my plan is to buy some pretty good ballasts and bulbs and to build the fixture myself. I wondered if you could recommend one or two ballasts. Can you comment on the 400W Universal Magnetic M135 Ballast -Pulse Start Metal Halide they sell on hellolights.com for $86.00? Any information you could give me about MH ballasts would be greatly appreciated. Should I use 10,000 or 20,000K
halides for my application?<10K or 20K, the choice is yours. The Universal ballast will work fine, especially if your on a budget.  The electronic ballasts do increase bulb life and intensity.  Another ballast would be the "Blue Wave brand".  They usually sell for about $100-115 on the internet.  James (Salty Dog)>I really appreciate your site and the Conscientious Marine Aquarist, a great resource that I consult often. Thanks very much,
Justin Armstrong

LIGHT CONTROL
Sat, 5 Feb 2005
Hi there.  I am currently having problems finding a timer to control lighting needs.  Specifically metal halides and moonlight.  Do you know of any products that can control when the MH come on and go off as well as control intensity of moonlight?  I know there has got to be some out there.  I tried CA,
Champion, MarineDepot, etc. to no avail.  Thanks for your help. <Tazzis, I have just the product for you.  It's called the Active Home Pro USB 2-way Home Automation System. The beauty of it is that you control the system with your PC.  It sends digital signals through your home wiring to turn on/off modules that you employ.  Dimming modules are available for MH/Power compacts providing your ballast is electronic and has dimming capabilities.  Best of all the basic system is $49.00 plus the modules you select to use.  Modules are anywhere from $14.00 to $20.00 depending on what you want.  You can turn the system on/off as many times a day as you like.  Use it also to shut powerheads off/on.  The site to go to is www.x10.com.  James (Salty Dog)>

Lights and protein skimmer
Thu, 03 Feb 2005
Hey WWM crew-A few quick ones. First, I just purchased a double 175 MH hood setup for my 65. I hung it above the tank because I have no hood. (tank is built into the wall with a dedicated room for equipment behind it). There is a Plexiglas strip protecting the bulbs. Should I still keep it 8" above the tank, and should I remove the Plexiglas strip for more light intensity.<Keep the acrylic strip, it serves as a UV filter, and you could lower the lights some as long as the tank is still lit completely.> Second, I plan on adding a 38 gallon refugium. Can I put my protein skimmer (Remora Hang-on) in the refugium, and if so, should it go before or after the deep sandbed section.<I would put it before the sandbed.  James (Salty Dog)> Thank You
Brian Cooper

VHO--->HQI
I have read much of the info in the metal halide FAQ's and would like your advice.
<Will gladly render my opinion>
I have a std. 55 gal tank that is currently lit with 4 110W VHO's. I would like to add a clam, and I think I need MH lighting.
<Depends... on the species... its placement... your desires for rates of growth... other co-factors like water clarity, alkalinity, alkaline earth concentrations...>
I am thinking of installing a 150W double-ended 10000K HQI light on one side of the tank. I was thinking of retaining the 2 outside (front and rear) VHO's but I think the HQI fixture is too wide to permit that. is the 150HQI of sufficient wattage (and 10000K right temperature) for that end of the tank--or should I use a 175 or 250 MH?
<If it is for just the clam/s, I'd go with the lower wattage... if you think you might get very involved with SPS the higher... or two 175s... and a calcium reactor...>
I would then re-use my existing VHO ballast by installing 24" VHO's in the other end of the tank. While the canopy is totally enclosed, I have 2 ventilation fans installed, and room for 2 more if necessary.
<Good>
Thanks!  Ken Baker
<Ken, do look into the added upkeep you will be inducing here... as well as the incipient operation costs... for electricity, lamps. Bob Fenner>

Re: VHO--->HQI
Bob--thanks for your quick reply. You've given me the info I needed, and will do a bit more research and introspection on planning for future livestock before a final decision on wattage. Having said that, there seems to be lots of "opinion" here in the FAQ's that 250W is a bit too much for 15" depth (std 55gal minus 3" of substrate).
<Mmm, do check this... most stock 55 shows are 22" in depth>
Given the inside height of my canopy, I will have the bare minimum 6" between the bulb and the water surface.
<This IS of concern... for waste heat, light spread... as well as dangers of splash and spray on the lamp/s>
Here in central Indiana we are fortunate to have reasonable electricity rates, so adding an MH won't kill me!
<We'll see... a dear friend owns a shop here in S. Cal... told me folks just brought in and dumped their MH's when rates here trebled (more thievery by the Gov't really)... and simply walked out... Bob Fenner>
Thanks again, Ken

HQI lighting and UV
Hello Bob, Compliments on the great site with all this useful info. What I was wondering: I have a 250 Watt HQI bulb, do I need to use a lens to filter out UV rays? or is this optional? Thanks, Eugene. 
<AdamC here. Thanks for the kind words! Ordinary glass blocks UV, but quartz glass does not. Although it is not technically correct, HQI has become synonymous with "double ended". All double ended lamps require UV shielding because the outer cover is quartz and does not block UV. All double ended fixtures should include an ordinary glass cover which will safely block the UV. Single ended lamps are build with ordinary glass, so they don't require shielding. Best Regards! AdamC.>

Metal Halide Question
Hello, <Hello Brent>
     I am setting up a 90 Gallon 24" tall by 48" long tank.  I have installed two 250 W metal Halide 1400K lights.  When the lights are on, shining on the white rock and the white sand it seems pretty darn bright, almost to the point that if you are up close and staring into the tank it kind of seems like it could hurt your eyes.  Is that possible? <Only if you looked directly into the light.> If it is too bright, does this lessen over time as photosynthetic organisms begin to cover the rock? <It will.>
     Also, I need to install some fans but I'm loathe to cut holes in the sides of my nice maple canopy.  Is it possible to install them on the rear of the spider reflectors, somehow attached to the rear of the canopy hanging down by a bracket as to vent the heat out the back of the aquarium?  If so, how far away from the wall should I have the aquarium from the wall; 6", 8" or more? <Three inches would be enough.  I wouldn't exhaust the air in an open back lid.  It's much better to have the air blow across the water.  And yes, your plan should work.
James (Salty Dog)>
Thanks, I read your site all of the time
Brent

Reef Lighting...Which Wattage? - 05/26/05
Thanks. I just bought a well established 140 gallon reef tank with 19 fish in it and about 7 different corals and polyps. Everything is running fantastic, the only this is that they have two different metal halide bulbs....One side is a 175 watt 20k and the other is 400 watt 20k....Which one should I replace? Is there a benefit in have one over the other? 
<My personal opinion is there are very few instances where you really need 400 watts of halide lighting...and I'm an Acropora reefer! I would probably go with 250 watt setups on this system but given your current equipment, my vote would be to replace the 400 watter with another 175 watt setup (you do realize you'll have to replace both ballast and bulb, yes?), and use 10K bulbs in both. Research your corals and place the ones with greater light requirements higher in the tank and I'm betting you'll be fine.>
Thanks
<Regards, Eric R.>

What's the Diff?  Temperature Difference Between Metal Halides
Hi, I know that metal halides run hot but is there much of a temperature difference between the 400 watt and the 250 watt halides ? Thanks
<Mmm, yes... about 150/250 more... Bob Fenner> 

HQI Ballast - 06/03/05
Great thanks.  I am looking into drip system for Kalk.
<<Great!>>
One more thing on Metal Halide.  What is a HQI ballast versus a regular ballast?
<<Generally speaking, ballasts designated as "HQI" will run about any type of metal halide bulb (single- or double-end...from any manufacturer) within its given wattage.  A "regular" ballast will usually only run the single-end bulbs and are sometimes limited to certain bulb/ballast maker combinations.  Best to check the specs of the particular ballast in question to be sure.
The HQI is more expensive but I am sure it has a good reason.
<<If I may...my suggestion would be to buy HQI electronic ballasts.  These will run just about any bulb you care to use (within the correct wattage of course), will run cooler than non-electronic ballasts, and will save you a bit of dosh in electricity consumption.  They will cost more initially, but are well worth the expense in my opinion.  Electronic ballasts manufactured by IceCap Inc. are my absolute fave.  Eric R.>>

Metal Halide Shield
Hello Crew,
I just wanted to thank you for the wonderful service you provide! I have a question regarding my metal halides. I am in the process of constructing a hood for my new lighting (2x250 watt MH and 2x110 VHO). I had always planned on using a glass shield under the lighting fixture. I have been told I would have to use tempered or heat treated glass in the
hood. Is this correct? 
<You would just need tempered glass, a little harder to break.> 
Someone on reefcentral suggested Lexan for superior UV blockage. Would the plastic melt? 
<If your halides are eight inches away and properly sized cooling fan(s) are used, this should not cause the Lexan to melt. I would use 1/4 inch thick acrylic.> 
Can I get away with using regular glass? 
<Glass does not shield UV as effectively as acrylic.> 
Do I even need a shield if my lights will be 8 inches off the water surface? 
<Yes> 
Any insight you could provide would be much appreciated. 
<You're welcome. James (Salty Dog)> 

Re: Lighting?
Sorry about the name Bob. On the way to bed and couldn't really see straight.
<Happens>
It was a very long day. If it would be alright, I have a few questions for you. My friend happens to be my LFS and says that she can give me the metal halide upgrade for 90 bucks. I am guessing that I should just replace the old system with the metal halide. The system is complete with the ballast, reflector, and bulb. Will this give me full spectrum light (actinic) or do I need to buy more light fixtures. The system is 240 watt. Is it worth it? Also, is it possible to keep Euphylliids? (130 watts) Thank you so much.
Brian
<All this is posted... on WWM... there are full spectrum and not MHs... Is worth it IMO... good for Euphylliids... Bob Fenner>

Halide Lighting (Mixing Ballasts And Bulbs?) - 05/27/05
Thanks for the info.
<Welcome>
So I talked to the previous owner and he said they used to have two 400 watt bulbs but by accident bought the 175 and kept it and they used the same ballast as the 400, they didn’t change it at all.
<Hmm...I have heard/read about ballasts that claim to "adjust" to the wattage of the bulb, usually sold by greenhouse/hydroponics suppliers and geared toward very high wattage bulbs (400w/600w/1000w). I suppose it's possible you have one of these?>
Do I still need to change the ballast?
<You need to determine for sure which wattage(s) the ballasts are designed for and use a bulb of the correct wattage. If the ballasts are not clearly marked, contact the manufacturer. If you are running a 175w bulb on a 400w ballast it's my opinion you are risking catastrophic failure (explosion) of the bulb.>
One more thing, what is the difference between 10k, 14k and 20k?
<The "K" refers to the "Kelvin temperature" of the bulb which correlates to color rendition. The higher the Kelvin, the "bluer" the light appears. I recommend 10K bulbs due to their crisp white appearance, which to my eye, provides a more natural appearance than the more blue appearing 14K or 20K bulbs. BTB, even a 6.5K bulb contains more than enough "blue" for the animals we keep, thus choosing a Kelvin temperature generally becomes a matter of what is pleasing to us humans <G>.>
Thanks
<Welcome, Eric R.>

Lighting
Hi WWM Experts, <Hello, Chris>
I apologize for asking the type of question you have probably been asked a million times.
I'm on the verge of ordering lighting equipment from overseas (I live in South Africa) and I'm a little scared to order the wrong things (which won't be so great considering our exchange rate to the dollar !), so I was hoping you can give me your insight on this. The dimensions of my new reef tank is 64"x24"x24", holding around 150gallons of water and I would like to keep a mixture of soft and hard corals (we don't exactly have a wish list yet). After doing a lot of reading on your site and in Mr. Fenner's book I understand that I will need in the region of 3-5watts of lighting per gallon for my setup, which gives me 450-750watts. My understanding is that metal halide lights cover an area of about 2 feet with the 175W MH ideal for tanks up to 20" deep and the 250W MH to about 30". So in my mind the options are:
a) 3x175W
b) 3x250W
c) 2x250W
I have 2 questions - 1. Am I on the right track here in choosing Metal Halides? 2. Can you recommend one of the above 3 options, or perhaps something completely different?
I'm leaning towards 3 x 175W plus a couple of actinics, but it would really be great to have some input from the experts here.
<Chris, for hard corals and the possibility of clams, if the interest arises, I would go with the three 250 metal halides, nothing lower.  James (Salty Dog)>
Thanks again for all your support.
Chris

Lighting
Hi guys and girls. <Hello Nick> All of you are awesome and thanks for  helping all of us. <You're welcome> I have a reef aquarium with live rock and corals.  I need upgrade my lighting so I can get some maxima clams and hard corals.  My tank is a 60 gal. Tall narrow corner tank that is like 24 inches tall.  I bought a 400 watt pendant metal halide from eBay that someone took down from their warehouse  roof.  I have read that the pendant MH is not recommended for a good light because of the narrow beam. but because my tank is tall and narrow would it be ok for my application? <I think it would work.  Of course you won't be able to use the bulb that came with it.  You will need to replace the lamp with a 10K or higher bulb>. I don't want my water to get hot so how far would you recommend putting the light from the water since I have wattage to spare. <First, you won't have wattage to spare.  Maximas require at least six watts per gallon.> And would this be too much light for hammer and xenia
corals. <I think they will be fine.  As far as heat goes, I would start by keeping the lamp 10 inches from the surface and monitor temperature.  You may even need a cooling fan blowing across the water.> Thanks for the help and I hope you have a great day! <James (Salty Dog)>

Metal halide lighting 07/01/05
I have a 10 K 175 watt metal halide light system and was wondering if I should have glass tank lids on? <Yes, need to filter out the UV.  James (Salty Dog)> <<Mmm, actually, many MH lamps come made with their glass acting as such filters. RMF>>

Metal halide ballast 30 Jun 2005
I was thinking about purchasing a second hand metal halide retrofit kit.  It is a 2x250 watt kit with Iwasaki 6500K bulbs.  At the LFS they said it would need new bulbs in a couple of months.  However, they said that the ballast would only fire 6500K bulbs.  I have never heard of this before, should I be safe and order the same bulbs or could I try a 10K. <Eric, the color temperature has nothing to do with whether the ballast will fire the bulb or not.  I've never seen a ballast labeled "For 6500K only", or vice versa.  James (Salty Dog)>
Thanks for your time and help, <You're welcome>
Eric

MH Question!
<Ryan Bowen with you this morning>
I am setting up a 68 gallon reef ( 48x18x18). I am wondering what MH lighting to use. <Lots of choices, eh?> By the Book of Coral Propagation, <One of my Aqua-Bibles as well> I should be able to use 175 watt MH as the tank is only 18 inches deep. <OK> I plan on having brightly colored SPS and clams only. Will 175x2 work with 2 VHO's or would you go to 250x2 with VHO's? <Two 175's are perfect, as long as you are: A. Buying a quality electronic ballast, and B. Marking your bulbs on the calendar, don't miss a replacement.> Are the electronic ballast worth the extra price and do you think double ended bulbs are the way to go? <Haven't used double ended bulbs myself, but I have heard good things.  Try the forums over at http://www.wetwebfotos.com for some feedback.  As for the electronic ballast, it's a must.  It will save you money in the long run!>  To complicate the matter, I have a 400 watt MH retro from my previous tank. Would dual 400 watt MH be overkill? <Likely> I want to purchase the right thing the first time and not have to keep upgrading as it cost too much money in the long run. <I know it!  I think you're on the right track.  Lighting is certainly important when you're raising photosynthetic animals, but don't forget about current!  It's nearly as important.  Good day, Ryan>
Thanks
Wellington

New Metal Halide Lighting design?? - 1/25/04
Hello Crew!
Unbelievable site! <Yes indeed!> I've just devoured Mr. Fenner's book and I use this site
daily. <Great to hear>
I am a fairly new aquarist and have some questions regarding MH lighting. I specifically interested in understanding the reasons for the height recommendations regarding MH lighting. <Well, heat for one, moisture, and intensity.> I've seen the recommendations for 6-10 inches off the water for 175 Watt and 12 inches for 250 Watt lamps. Are these heights designed for safety, light levels, or heat dissipation? <All the above, mate> I realize that the short answer is probably "yes". Why would you get a larger wattage lamp and then raise the height over the tank? <I think you can "guess" the answer here as well. The greater intensity does little in dissipating the heat but the output even at a few inches is still great enough to promote growth in the coral thus the elevation in the higher lighting fixture> I am in the midst of designing a 125 gallon reef tank. I'm also designing my own MH light fixtures. <Ahhhhhh> The fixture utilizes a "cold light" reflector that reflects 95% of visible light but transmits 75% of Infra Red light (heat). The fixture also utilizes a "hot mirror" as a lens that the lamp shines through. This "mirror" transmits 95% of visible light but reflects 75% of IR (heat). <OK> The result is a lamp that produces only about 15% of heat at the lens of a "normal light". The balance of the heat ends up behind the reflector where it's easily dissipated into the air via a chimney type heat sink. <Sounds interesting.> I've designed the light much like a fat, squat version of  a "Mag Light". The entire fixture is watertight (indeed submersible). <Hmmmmmm> Given the fact that this light adds very little heat to the aquarium and the fact this it is watertight, could I place this light very close to the water (I'm thinking 3 inches) and use a lower wattage bulb than I normally would? <Well, when designing a "new" type of light I suggest you experiment as much as possible> I realize that there are many factors that affect the light decisions. <You said a mouthful> I'm interested in a apples and apples comparison. <Well, not being a light guru or designer for that matter I only have the basics of lighting under my belt. Why don't you produce such a comparison? Read some of the articles by Sanjay Joshi around the net and in some of the old salt aquarium review periodicals.> In other words, given an aquarium with a perfectly matched "normal" 250 Watt lighting system, could I use a lower wattage bulb, hung closer to the tank, using my design, assuming all lighting characteristic were identical? <Is possible. In fact I have seen some pretty amazing coral tanks without the use of Metal Halide or even Power Compacts for that matter. I suggest you create a hypothesis, and set up the experiment yourself and publish your studies. Your basic theory seems plausible given light output but remains to be seen until your "test" device is ready for trial. Give 'er a go! ~Paul>
Thanks so much for your insight and fabulous site!
Jim

Adding MH Lighting 2/5/04 
Hello again! You guts are great. Thanks for the help in the past. 
<Hi Jim. Glad you have benefited.> 
I have a 120 gallon tank that is 4'x2'x2'. I currently have 700Watts between PC and VHO. I want to get rid of the PC and change to a 250Watt 10K MH (I already have the MH). The problem/concern that I have is that I currently have my lighting under a hood. If the MH fixture can fit under the hood, will it be okay to run with two 4'' fans for cooling? 
<It should be, but it is hard to guess. Depending on where you live, whether you run A/C in the summer, use a chiller, photoperiod, etc., the fans may or may not be enough to control heat.> 
Will there be an issue with placing the fixture on top of the glass cover? 
<If you meant the glass aquarium cover, yes. The heat from the lamp may dangerously overheat the glass cover if it is too close. Also, most reef keepers don't run glass tank covers because of the amount of light the block, even when clean.> 
Another idea that I had was to remove the bulb from the fixture and mount it to the top of the hood with a piece of sheet metal to deflect the heat from the hood and still using the reflector. I would still use the fans to cool the light, but I am not sure if this is a good idea. Any other suggestions to improve lighting and still keep everything under the hood? 
<If your MH is contained in a pre-made fixture, I would try to use the fixture as is. It should be at least a few inches from the water surface to protect it from serious splashing. I would consider cutting a hole (or other wise re-engineering the hood) and recessing the fixture in the top of the hood before I would dismantle the pre-made fixtures. Best Regards. Adam> Jim Martz Sr. 

Lighting 2/9/04
Thanks for your quick response.  Just one more question before I spend more money on this tank!  I asked the guy I trust the most at the LFS why he recommended 400w.  I told him what you had said about the tank needing to be more then 30" deep to even consider them.  He told me that he recommended them because my tank is 27" deep plus the canopy being 10 1/2" deep = about 37" deep.  I do not plan on buying another canopy... so with that being stated would you still recommend I reduce my W's?  
<its tough to say... the corals you are keeping have no need for such bright light and you do not need to pay the extra electricity for a flawed canopy/installation. But then again, the cost of correcting it will be a short term expense that you may not wish to suffer. If you think you may get a bigger tank in the next few years, then do keep the 400 watt lights (begrudgingly <G>)>
Again last time I will ask, and from all the reading on the WetWebMedia site, I really do love your sense of humor...keeps the reading entertaining... thanks again, Phil
<no worries my friend. The corals will adapt likely so. And if you can endure the heat (more fans to exhaust perhaps) and expense, no change is needed. Anthony>

Metal Halides
Greetings Anthony, Bob and the rest of the crew. <Cody here today.>Today's question is in regard to MH lighting. I've perused the various boards on WWM regarding MH lighting, but sadly, the more I read the more confused I get. My 75G reef has been up for one year as of this week. All is well thus far. I have been going with softies (xenia, polyps, leathers, etc) with the exception of a couple of open brains (trachys). My wife has been insisting on a clam from the time I set up and cycled the tank. I explained to her the need for more intense lighting and she has finally broken down and given the okay for me to procure the halides. Through the drygoods forum at RC (can I say that?) <Of course, I spend tons of time there myself!  They are a great place for info with many different opinions.>I found someone who was upgrading his system and letting go of a pair of 250W moguls w/spider reflectors, ballasts, etc. He is including 3 mo. old (so he says) bulbs but isn't sure what brand they are. He says the lighting is a bit on the yellow side. First question is, what brand and/or type of bulbs would you recommend. <This all depends on personal preference.  Every one has different opinion and you sill have to go check out some tanks with different bulbs.>If I use bulbs with a bluer hue, should I still run actinics or will the MH bulbs over-ride them? <If you use a very blue bulb like XM's you shouldn't need any supplements but again it all depends on personal preference and is a trial and error kinda deal.>Currently, I have a Coralife 48" fixture with 2 65W 10000K and 2 65W Actinics plus 3 additional 65W 10000K in a home-made set-up. If Actinics should be used with the halides, I figured I could use the home-made set-up to house them. Next, in going with the spiders, what about the lack of any type of UV filter on the fixture? Is this something that needs to be addressed? <I would definitely put some type of UV filter over these.>Finally, how close (or far) should the MH's be mounted from the top of the tank, and if I do use the PC Actinics, should they be mounted lower or at the same height as the MH's? <MHs should be about 8-10 inches away and the actinics can be mounted closer.>Oh yeah. One more thing. Should I move the corals to a lower level in the tank and gradually move them up or just begin using the Halides on a shorter cycle and gradually increase the time they are on? <Definately, I would move them to the bottom (the brains should already be there) and gradually move them up so they can adjust to the new lighting.>Thanks once again for all of your help. I look forward to hopefully meeting some of you guys this June in Chicago.<Thank you for writing!  Don't know if I'll make it but there will be quite a few of us there!  Cody>
Greg
Berkeley, IL

The Right Light?
Dear Crew:
<Scott F. your Crew member today!>
Thanks again for the great website.  I have read your FAQ's and articles about MH lighting with great interest.  Here is my situation:  I currently have a 55gal (48x13x20) tank w/130W PC's.  I am going to get a bigger tank this year, probably a 125 (72x18x22).  I would like to keep some clams & SPS, so I am looking at MH.  Also, I believe HQI DE bulbs and fixtures will give me the best for my money.
<I agree!>
Now, according to Bob's response in one case, with "some" clams and SPS, I should be able to go with 175W lamps. However, I have only seen HQI in 150W and 250W flavors.  The difference in price is about $20, so it would seem wise to get the 250W.  However, I do not wish to have the extra light if I do not need it.  I could probably go with 2-150W lamps for the 55 now, and get an extra one when I get the 150gal.  I thought about 2-150's and then the one 250 later, but I am not sure how I would feel about the spotlight effect (I assume there will be one).
<With well-designed pendants, such as Sunlight Supply's Reef Optix III's, or the new PFO mini pendants, the "spotlight effect" that you refer to is usually not noticeable. I use a mix of 150watt and 250 watt HQI pendants over a 20" high tank, and have been quite pleased with the results. It's never a bad idea to look into the 250 here. Clams do require intense light, so at least one 250 would be nice to experiment with!>
Before I forget; I know some of you don't like to say, but which would you pick of the 2 choices I have for either 150W or 250W:
1) PFO HQI ballast, Aqualine10K DE HQI Bulb and PFO HQI Mini Pendant *OR*
2) IceCap Electronic HQI Ballast, Ushio or Aqualine (AB) 10K DE HQI Bulb and Sunlight Supply Reef Optix III Plus Horizontal Reflector.
<I like #2, and use this combo myself>
About choice #2, I have seen some vendors insist that the Sunlight Supply Reflector must run with Blue Wave Ballast.  If this is true, what makes the IceCap okay in this case?  Is there some sort of overdriving or trickery going on here?
<Not true at all. Myself and many of my reef nerd friends use the RO III/Ice Cap combo with great results! I'm not sure if this is true or not, but somebody "in the know" within the aquarium halide lighting market told me that the Blue Wave ballast is essentially the Ice Cap in a different housing...Again, I don't have any verification of this, but it may be worth checking out>
Hey, thanks a million, Rich.
<My pleasure! Regards, Scott F>