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 placement, angle reflection question 01/14/2008 Greetings Dear WWM Crew, <<Hello Brian, Andrew here>> First, I'd like to thank the membership of the WWM crew for the enriching leadership you collectively provide. I have kept freshwater (Cichlids) for four years now and have often visited this site for reference. During these freshwater years I have immensely enjoyed pouring over the great variety of detailed topics relating to marine systems as well. Long story short...(and after reading Bob's excellent text (CMA) cover to cover) I'm now venturing into the saltwater realm. Today, I have a lighting and light-fixture-position/hood-design question that neither my reading the FAQS nor searching the archives has answered. I'd be most appreciative of your assistance. <<Lets see what we can do then>> I recently purchased a used, 200gal (84 x 24 x 24) Oceanic RR (Dual "Megaflow"...which by no means actually IS "RR") and am gradually acquiring components, doing research, etc, that will enable me to reach my FOWLR and, ultimately, Reef tank goal. The tank came with an exceptional stand but no hood/canopy. As a somewhat advanced hobbyist woodworker (furniture), I intend to craft my own. As I collect all the necessary aquarium equipment, I am trying to "buy once" and obtain components that will provide prolonged service across the spectrum (no pun intended with my question) of my development as an aquarist. To this end, for lighting, few solutions seem to adequately fit the 84-inch long dimension of this tank. Thinking that an assemblage of separate lighting fixtures would best suffice, I have acquired 4, 20-inch, Current SunPod 150W/14K (HQI) MH lights which I intend to integrate into the canopy design. <<As a note, a single MH bulb is good enough for lighting 2 feet of tank length>> My question (at long last) is this: My plan is to design the canopy mount such that the Sunpods are positioned end-to-end along the 84-inch length of the tank. However, in order to maintain some nominal distance between the ends of the fixtures (specifically, to keep the integrated cooling fans located on the ends of the fixtures free from obstruction), some fixture offset is, I believe, required. For clarity, the concept is that the fixtures on either end would be centered (front to back) and the two fixtures in the center of the tank would be positioned forward (approx. the 8-inch fixture width). When offsetting the SunPod fixtures in the center, a nominal space would be left between the end-fans of these as well. In shifting the center fixtures forward, they would be closer to the front of the tank and so I was considering angling those fixtures slightly inward (perhaps 15-20 degrees)...to direct more light output into the tank and less through the front glass (such as will occur by being closer to the front and per reflector-coverage design). I am concerned about the resultant amount of light reflection that might occur by angling these fixtures, if the reflection would be significant (considering that the water surface is constantly irregular anyway when good circulation is achieved). So, I am wondering if the angling of light fixtures has been successfully done in the past and if a deleterious effect (light loss to reflection) will result by doing so? I've attached a rudimentary diagram to help explain the concept. Any advice would be most appreciated. <<I would be tempted to only use three of the four fixtures that you have bought. Your tank is 7 feet long, 3 of the lighting units will be fine, spaced evenly with 4.5 inches from the outer edge of the lamp unit to the end of the hood. If you use the method you have mentioned above, the light will not be adequately dispersed in the aquarium, basically giving you low lighting at the front as well as an irregular lighting pattern inside the tank, and I think this will greatly reduce the viewing pleasure of the aquarium>> Thank you very much for your time. Best Regards, Brian. <<Thanks for the questions, A Nixon>> Re: Lighting placement, angle reflection question 01/16/2008 Good Morning Andrew, Reference 01/14/2008 Lighting angle question <<Good morning again Brian>> Thank you so much for the fast reply. <<No problem>> The simplicity of your advised solution is like that "should have had a V8, bonk me on the head" commercial. No need to overcomplicate, duh! In defense of the apparent fog that surrounds my decision making, :), I'd actually considered several options including going with a single, 72-inch, 3-bulb SunPod fixture or, as you suggest, just using 3 of the separate fixtures. However, the more I looked at the dimensions of the SunPod product line, the widths of the fixtures and locations of the actual bulbs (bulb effective centerline within the housing and "centerline" of overhead/hood placement), the more confused I became. I have seen the common reference to a single MH bulb's "effective" ability to cover 2ft of tank bottom. Presumably, this reference takes bulb height (distance from water surface), substrate depth (i.e. DSB of 4-5 inches), and water column diffusion factors into account. In my case, if I have a 4-inch DSB, place my bulbs 8 inches from water surface and have a tank with 24-inch height dimension, then I am looking at a 28-inch distance from bulb to substrate surface. <<A single 250w metal halide bulb can penetrate down to 24 inches when mounted 8 inches above water level>> Per the common reference to a single MH bulb's ability to "effectively" shed light on 2ft of tank bottom, my thought would be that the centerline(s) of MH bulb placement needs to occur at 12-inches from either end of the tank and at 24-inch increments between bulbs for multiple bulb fixtures. I'm thinking that it is particularly important that the bulbs at either end of the tank are placed 12-inches from the tank end so that aquascaping, such as taller live rock structures stacked to conceal overflows, are fully illuminated on the ends (outer sides). <<I agree, we need the lighting as evenly spaced / spread as possible>> Many of the products I see available, such as the 36-inch dual bulb SunPod for example, place two bulbs (bulb centers) approximately 12-inches apart...meaning (presumably) much greater (concentrated) illumination in some areas of the tank and considerably less illumination in others. <<That happens a lot with multiple bulb fixtures>> Part of my reasoning in selecting the 20-inch SunPod was that bulb centerline is 10-inches from the end of the fixture which would allow hood placement to achieve an effective 12-inches of bulb centerline from tank end (i.e. the live rock illumination concern noted above). <<Valid point>> Considering all of this "over thinking" I wonder if, in my case with the 7ft tank, center brace location, etc, a return of the 4, 20-inch SunPod fixtures and purchase of 2, 36-inch (dual 150w MH bulb) fixtures would be worth considering in order to achieve the most evenly concentrated distribution of light (bang for the buck)? What say you? <<I would agree that would be far better in the situation you have with the hood and brace setup. I would go for the 250w bulbs as this will provide you with more punch of light down towards the bottom of the tank>> Again, many thanks for your time. Your advice is most appreciated. Warm Regards, Brian. <<My time is your time Brian, many thanks for the questions. A Nixon>>

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