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FAQs about Light and Lighting for Marine Systems, Fixture Selection 3

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Related FAQs: Marine System Lighting, Marine System Lighting 2, FAQs 3, FAQs 4, FAQs 5, FAQs 6, FAQs 7, FAQs 8, FAQs 9, FAQs 10, FAQs 11, FAQs 12, FAQs 13, FAQs 14, FAQs 15, FAQs 16, FAQs 17, FAQs 18, & FAQs on Marine Lighting: Fixture Selection 1, Fixture Selection 2,  (incandescent, fluorescent, MH/HQI, LED, natural...), Lamp/Bulb Selection 1, Lamp/Bulb Selection 2, (See Fluorescent, LED, MH... below), Installing, Waste Heat Production/Elimination, UV Shielding, Measure, Troubles/Repairs, By Manufacturer Make/Model: & Actinic Lighting, Metal Halide Lighting, Fluorescent Lighting, Compact Fluorescent Lighting Small System Lighting, Lighting Marine Invertebrates LR LightingTridacnid Lighting

Many fishes don't like overly bright settings

Lighting question: 20k vs. actinic bulbs   3/19/13
I am planning a move up to a larger reef aquarium with softies and LPS and considering lighting options.
<What size display?>
Currently I have a very nice Aquaticlife t5 HO 4 bulb fixture with (2) 10k bulbs and (2) 20k bulbs in place of the actinics.
<How long have you had this fixture?>
 I love the look and the corals have done well. The 20k run 14 hours, the 10k 12 hours. What do you think of this set up?
<Firstly, not all 20k's or 10k's are the same as one another. Some will hold their spectrum much longer/better than others.>
Do you see any potential problems? It seems to me that 20k bulbs have more usable light than actinics, but I do admit that I find the whole lighting issue somewhat confusing.
<Haha it sure can be can't it. Some of these new full spectrum LED's are even more complex. Not all actinics are they same either. There are 50/50's, 75/25's etc, the lighting combinations you can have are vast>
 Thanks for your input.
<Your 4 T5's could be a ton of light for a shallow tank or they could be really inadequate for a larger tank. Lets figure out what size range of tank you will be upgrading to and go from there. NateG>
Re: Lighting question: 20k vs. actinic bulbs   3/19/13

Sorry about that. I am moving from a 46 gallon to 75 gallon. I got the fixture three months ago. The 10k bulbs are original, the 20k are Giesemann that where put in January.
<Nice color mix. I bet that looks great>
The fixture is 36 inches long, the new tank will be 48 inches long.
<Unless you raise the fixture a solid 6+ inches off of your tank, your top corners will be without light. Some people even prefer this effect. You should have enough light with your 10k 20k combo to have some less light demanding corals by your sand. I wouldn't recommend 2x 10k and 2x actinic over a 75. Especially if its a 36" fixture.>
Karen Adam
<If you find yourself in the market for a larger fixture, it is well worth the investment for some nice full spectrum LED's. No more of the $80+ a year in bulbs right. Less heat, less ac, less electricity=more $=more frags! NateG>

Metal Halide Vs T5 HO    5/28/11
Hello guys and gals! John here. I hate to add to the large amount of questions you receive and answer. I also know that reef lighting is an open for debate topic. I am currently using a Current T5 HO Nova Extreme fixture on a 90 gallon (48" long) Mixed reef with clams. I am wanting to use that fixture for a propagation tank of LPS. My consideration for a replacement is either an ATI 36" 8 bulb fixture, with individual reflectors, or a 48" Ice Cap MH. I have read The Book Of Coral Propagation. I am reading the Conscientious Marine Aquarist but I can't find the answer I am looking for.
I guess I am looking for someone more knowledgeable than myself ,that is not trying to sell me something, to give me advice. Thank you so much for all of your help in the past and future.
<Mmm, well all three fixtures could/would work... a bit of an equation/expression is the amount of energy and time you're interested in investing in for the amount of growth you'd like... the MH fixture here will get you the most growth in shorter time, but with more operational cost (a few tens of percent)... the HO an intermediate time frame/growth... and your present fixture last... Is this response satisfying? Bob Fenner>
Re: Metal Halide Vs T5 HO    5/29/11
Yes and no. I guess I should have been more specific. Lighting is such a tough topic. I have Crocea and Squamosa clams but I would like to add Maxima. according to Anthony Calfo, Crocea clams are the most light demanding. everything else I read and hear says Maximas need MH.
<Not necessarily... but as you state, high intensity...>
I am a bit confused, since my Croceas are doing well. I don't want light overkill but I would like the maximum light for growth, health and aesthetics of my invertebrates. Would Metal Halides be overkill?
<Mmm, better to have you search WWM re PAR, metering... How to put it/this... it's not the technology or means of producing photonic energy that is important, but the cost of production, application (depth, water clarity, colour....) that's important>
I suppose that is really what I was after. My tank is 48x24x18.
<... and so sometimes Maximas, Gigas clams are "placed up higher" in the water column>
Thanks again for your quick response
and helpful info.
<Welcome. BobF>

LED vs. Metal Halide Lighting/Reef Lighting   6/13/10
I couldn't find anything specific in your articles comparing these two light sources, and I'm looking to go LED.
<Because this innovative lighting is rather new, we do not have much information on this.>
Right now I am running a Hamilton 2x175 MH 10,000k / 2x110 VHO actinic over my 125 gal. with success, but would like to cut my power usage. I read in one place that LED has about the same lumens to watt ratio (about 90-93) with greater useful light energy, but cannot find more sources to verify.
<There are many systems out there ranging from simple LED strip lights to full blown modular systems capable of duplicating the light intensity of 400 watt MH systems.>
Can you guys help me? If LEDs are a practical alternative, what wattage should I have to replace my Hamilton?
<I wouldn't say that are a practical alternative at this point, as an LED system that would duplicate your MH system is rather pricey, but over time, the savings realized both in lamp replacement and power usage may well
justify their cost. I strongly believe that in the near future, prices will drop considerably on these systems.>
Also, my tank is 24" deep, so are LEDs going to penetrate deep enough to grow my corals? I have a large mix of soft corals, clams, polyps etc and would not like to harm them by cheaping out on elec. usage.
<AquaIllumination produces a modular system that would duplicate what you presently have in intensity/useful light. One 12" module consists of 24 LED lights and will draw about 75 watts from your wall. When you compare this to a 250 watt double ended HQI lamp, the light intensity is amazingly close, but the bad news is the 250 watt DE lamp, once warmed up, draws about 280 watts from your wall. Have a look here at pricing and detailed information.
Also read Dr. Sanjay Joshi's test review of this system and several others.
As you will see, the AquaIllumination system has by far the highest light output in terms of intensity.
<You're welcome. James (Salty Dog)>

Lighting recommendation -- 12/09/09
Dear WWM
I was wondering if I could get your input on these lighting systems.
First is AquaticLife 72IN 3-150W HID 4-T5 HO 6 LUNAR,
<A nice unit: http://www.thatpetplace.com/pet/prod/242484/product.web>
second 72" Outer Orbit 3x150 w/ PC Lamps and
third Belize Sun 72" 3 x 150W HQI + 2-T5 80W + 4 LED
The first two lights have internal ballasts, is there any concerns with
having internal ballasts?
<Mmm, no; not if the units are well designed, engineered, put together...
In some ways I prefer (especially over the Net, not knowing folks) that they be internal (vs. external, placed by the user, installer), as here they're likely shielded from causing harm, fire>
Does the HID lamp really put out more light while using less power?
I'm also concerned with noise from the fans on the light, is one system quieter than the other?
<Mmm, don't know. I'd ask about on the usual hobbyist bb's re actual user input here, though I suspect all are very quiet>
What system has the better reflector and over all light?
With many thanks Dan
<Again, I don't know, have not seen these tested for such. It would not be difficult to check for these characteristics though... given PAR, Lux meters and the fixtures on hand. I suspect the Belize unit is the winner
just by reading the specifications. Again, for real gear input my standing suggestion is a careful/cursory asking about on the hobby bulletin boards like Reefs.org, ReefBuilders... Please do report back your findings here.
Bob Fenner>

Lighting Question/Selection 8/29/09
Hello Crew,
I am re-sending this email because I'm not sure it was delivered properly. If it has already been received and is being processed, please forgive me for the repetition.
<Don't believe we have received this before.>
I am writing to you for help with my lighting questions, as have many people before me! My system is a 90 gallon 24"H x 48"W x 18"D with about 100 pounds of live rock, about 80 lbs of sugar sized aragonite, 3
Amphiprion percula, 1 Centropyge bispinosus, 1 Pseudocheilinus hexataenia, some green Sinularia, Duncanopsammia axifuga, Pachyclavularia sp., some mushroom anemones, a few Zoanthids and a
Pavona sp.. I currently have a 48" 2 x 65 watt 50/50 daylight/actinic fixture for my lighting. I would like to upgrade my lighting setup and was hoping that you might help me to determine what type of fixture and
bulbs I should be looking for. I keep wavering between T5 and metal halide but I am having difficulty making a decision. I can easily accommodate a hanging fixture in either case. Some of my concerns with
the metal halides would be the heat generated and also the light spilling out from the fixture, let's call it light pollution. My tank is in our kitchen area which is also open to our living room and I am not concerned about the extra light in these areas, but I am concerned about exposure to this high intensity light for my family, most especially my little 8 month old girl who would be looking up at it all the time! Would I be able to suspend the MH light at a sufficient distance so that I would be able to provide adequate lighting for my
invertebrates and yet not need a chiller for my aquarium? My house is air conditioned, so generally the ambient air temperature is not that high. Would I be better served by T5 lighting, and if so, how many
bulbs and what combination of wavelengths/intensities should I be looking for? I would also like to add that my rock structure is also arranged so that I am able to put the invertebrates with lower light requirements under some of my overhangs and at the ends of rock structures so that they do not necessarily receive the highest intensity or direct lighting.
<Is all going to depend on the type of invertebrates you want to keep. In your 24" deep tank, most SPS corals are going to require high intensity lighting in the form of HQI/MH, the same goes for many species of clams also. If your intent is to keep medium light loving invertebrates, then I would go with a 4 lamp T5 fixture. If SPS corals and light loving clams are in your future, then I would go with an HQI/MH fixture. There are many of these full hood fixtures on the market incorporating cooling fans in the fixture itself.
With these fixtures, your little girl will not be able to look directly at the lights, and in that regard, I would steer clear of hanging MH/HQI light hoods, can cause damage to your daughter's pretty eyes.>
I am looking through literature on the WWW as well as your many FAQs on WetWebMedia, but these are complicated and dare I say, muddy waters that I am traversing so I would appreciate your assistance here.
<You may want to read here.
Thanks again,
<You're welcome. James (Salty Dog)>

Lighting Advice'¦Fixture Type/Wattage -- 08/24/09
Dear WWM
<<Hiya Dan>>
I'm looking for some advice on lighting.
<<Okay'¦let's see if I can help>>
I'm planning on buying ether a 72x24x24 or a 72x24x30 inch tank.
<<I see'¦and for clarity/others benefit, I'm going on the assumption this is the standard dimension presentation of LxWxH>>
I'm looking at also purchasing an Outer Orbit HQI 3X150w MH with 4x96w PC. Do you think this lighting system is a good make and would it be adequate for both tank sizes?
<<I don't have any 'hands-on' experience with these units and to be honest they're not my cup of tea (for this kind of money I would rather build a rig using a better MH reflector [Lumenarc or Lumen Bright], but I have heard others say good things about them. As for its 'suitability' re these tanks, yes, it probably will do just fine with proper considerations to stocking and placement'¦though I would prefer a 250w system here for increased versatility re>>
Keeping in mind that I have not made up my mind on what type of corals I would like to stock and don't want to be limited on what I can stock.
<<Then I would consider a higher wattage MH bulb>>
Also I'm considering in adding a DSB of 6 inches to the tank, how much would this change my minimum lighting requirements.
<<Keeping in mind you haven't decided on the organisms you're going to keep'¦and most reefers penchant to go with 'bluer' bulbs these days (myself included)'¦I would still go with a 250w fixture/system>>
Thank you, in advance
<<Happy to share'¦ EricR>>

R2: Lighting Advice'¦Fixture Type/Wattage -- 08/26/09
Do you consider Coralife Aqualight Pro Metal or Hamilton Technology Belize Sun Metal Halide better fixtures?
<<I might give Hamilton the edge in quality, though I think any real difference here is going to be in one's sense of aesthetics'¦that said, I like the look/style/design of the Hamilton fixture over that of the Coralife unit. EricR>>
Re: Lighting Advice'¦Fixture Type/Wattage -- 08/26/09
Thanks for the info and the quick response.
<<A pleasure to assist... EricR>>

T5 Compaq combo? 5/5/09
Reef Lighting
Hello Crew,
<Hello William>
I'm completely confused by the mixture of info and lack of numbers to judge by when dealing with light bulb types, and I could use your help (and please correct me if I list something as a fact that is actually wrong).
I have a 72 gal bowfront tank, which is 48" long by 13" deep by 24" tall.
I also have the Coralife (Oceanic) 48 " deluxe light with Compact Fluorescents. It comes with 2- 24", 10k, 65 watt bulbs and 2-24" actinics (which I assume are 65watt as well), for a total of 230 watts of lighting.
I've been told this isn't enough for sps.
<Would be borderline for most light loving SPS corals, but there are a few species this lighting could support. Most etailers will list light requirements for species of corals they sell. In your case, based on the depth of your tank, corals requiring "moderate" light should survive in your system.>
I've taken LUX readings with the CF (don't have a par meter yet). Just below the water surface it's 5800 LUX , and my sandbed is at 1300 LUX. I converted LUX to PAR (but I haven't found any listing for the compact florescent coefficient to use so this is a guess) and get something like 116 at top and 26 at the bottom.
<Photosynthetically Active Radiation, often abbreviated PAR, designates the spectral range of solar light from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis.
This spectral region corresponds more or less with the range of light visible to the human eye. Since we use lamps of the proper Kelvin temperature, I would be more interested in LUX values rather than PAR values for our purposes. I might add not to confuse lumens with Lux. Lumens is the total amount of light that a lamp is capable of generating, usually available on either the lighting package or from the manufacturer's data sheets. There are two values usually quoted for fluorescent tubes: initial lumens and design lumens. Initial lumens describe how much light it produces when first turned on. Design lumens describe how much light it will produce for a much longer term. After an initial 20 percent drop in brightness, the light output will slowly decrease over the lifetime of the tube. Lux is a unit of measure equal to lumens per square meter or, a measure of the actual intensity of the light falling over a specified area.
Because Lux depends on how the light gets from the bulb to the area, it can not be specified by the manufacturer, but must be measured by the aquarist.>
I need to bump my lighting in the tank. I want to add a single strip T5 HO fixture. This housing will be 3 inches wide, which is all the real estate I have left to sit a light on top of the tank. I estimate this new light will cost me around $140.
So here's the problem.
I can't figure how much more PAR this will add to the tank, and therefore whether it's worth it. I don't want to waste money by adding a light that really won't be felt, but I don't have the ready cash available to buy a whole new lighting system. I don't understand how to judge watts to PAR <Watts has nothing to do with PAR. The watt is used to specify the rate at which electrical energy is dissipated, or the rate at which electromagnetic energy is radiated, absorbed, or dissipated.>
between Compaq's and T5s and MH. Any help?
<If keeping SPS corals is your goal, I would wait till you have enough cash to replace the unit with a twin 150 watt HQI lighting system. Adding an additional T5 lamp for 140 bucks would not be a good investment.>
From what I've read, the new T5 HO's are just as good as MH's these days.
Is this true?
<Yes and no, will depend on the depth of tank and number of lamps used. In shallow tanks such as yours, the T5 HO is a good way to go. I personally like the look of metal halide lighting.>
If so, how do you judge how many bulbs you need? As I stated my tank is 48" long, 24" tall and 13" deep.
And lastly how do Compaq's compare to T5 HOs straight up?
<The T5's, in my opinion produce a larger light distribution pattern and produce more lumens watt for watt.>
Are 2, 24" 65watt 10k Compaq's equal to 1-48" T5 HO?
<No, we are comparing 130 watts to 54 watts.>
Are the CFs 1/2 as strong as the T5 HO?
<I don't believe to that margin, again, watt for watt.>
Are compacts equal to the older T5s?
<Likely close, but the T5's have an edge on efficiency.>
These are the kind of facts I could use right now.
<I suggest you read here and related articles/FAQ's.
<You're welcome. James (Salty Dog)>

Lighting and DSB'¦T5 vs. MH -- 03/17/09
Hello everyone.
<<Hiya Steve>>
I am looking into upgrading from an Aquapod to a larger system. The wife has 1 unchangeable limitation of length being a maximum of 36".
<<I see (dang women [grin])>>
So what I am contemplating is either a 36"x24"x24" which is 90 gallons or 36"x24"x18" which is 65 gallons.
<<Same footprint, eh'¦might as well go for the added volume then, especially if considering a DSB>>
Also she wants a canopy for her own aesthetic reasons.
I would like to be able to keep clams and various types of corals. I will be using at least 1.5lbs per gallon of LR,
<<Do be sure to leave room for the fishes to swim/corals to grow>>
refugium, sump.
<<Excellent'¦and both can be used to house live rock (if needed) to keep the display from being overcrowded re>>
I would rather avoid a chiller.
I live in Orange County Southern California and the normal temp is under 90 most of the time. I do have AC in the house. I would also like to keep my electric bill down.
<<Wouldn't we all'¦>>
I would rather have the 90 gallon tank of course and this brings me to my question. If I go with the 24" deep tank and 4" DSB would a 8 X 39 Watt T5 HO lighting system with 4 10k bulbs and 4 actinic be enough to penetrate <to> clams <and> corals at sand level or would I have to go metal halide?
<<With some caveats, yes'¦ I would recommend a 6 to 2 ratio of 10K and Actinic bulbs. I would also suggest 'individual' reflectors for the T5s if possible, along with placement close to the water's surface. Do also consider the careful placement in the water column of livestock based on species/lighting requirements>>
If metal halide should I use 2 175watts or 2 250watts?
<<The smaller wattage would suffice>>
Should I decide to go with the shallower tank then could I use the T5's?
<<Not necessary'¦especially considering the addition of the DSB>>
Also should I have a lid between the lights and water?
<<I would not place anything over the tank to hinder light transmission OR gas exchange>>
I also don't mind installing fans in the canopy if necessary.
<<I would figure on doing this'¦regardless of the lighting option you choose>>
Also if T5 setup is ok will it penetrate <to> the DSB?
My last question pertains to lighting as well; depending on what light setup you recommend the canopy is available in 2 different heights 10" and 12"?
<<If your preference is the T5 lighting, choose a canopy that lets you mount these closest to the water's surface (ideally, within 3-4 inches). If you choose metal halide, either canopy will likely serve>>
Thanks for all your help.
<<Happy to share... EricR>>

Lighting Choices... reef  9/26/08 Hi everyone. I have a lighting question for you. I have looked at your site but the more I look the more I get confused. I was reading this article from Bob http://www.wetwebmedia.com/marine/setup/lighting/index.htm and it states in his opinion that full spectrum florescent lighting VHO is the best most appropriate lighting. <In some situations, less so nowadays.> But then when I read more into other articles others there answer say that PC and VHO are basically the same but PC has more density than VHO but Metal Halide would be the way to go. <Again, it depends on your system and livestock.> This is my plan and then you can give me an idea if you don't mind. I have a 55g that I want to move over to a 125g AGA that I got a few months ago. I have finally finished the sand bed and plumbing and want to start on the light. The light I have now on my 55 is a Odyssea 260w CF and I don't think that will be enough of my 125. I am going to build a canopy and was planning on pulling the fixture apart to put in there but again I don't think that is enough. I was planning on putting some DIY MH till now. It has a 6in sand bed right now. All my stock is still in my 55 which is a 4ft Zebra Eel (reason why I need to switch to my 125) 1 Clown, few Dempsey, Angel, butterfly and yellow tang and a few sps. <Yep, time to upsize!> I want to be able to really stock this once its up and going to lots of coral. <What corals do you wish to keep?> What is you recommendation on the light and how much (wattage, quantity, etc..)Also don't want something that will bring my electric cost up. Single parent. <More wattage equals more power used regardless of bulb type. For what you are looking to do you may want to consider T5 bulbs. They tend to impart less heat into the water and are as energy efficient that you can get right now (except for LEDs, but these are big money). How much wattage depends on what you wish to keep. A little research on your part regarding your desired livestock will answer this.> Been doing this for about 5-6years so I'm not really new to all this. Thanks!! Bill M <Welcome, Scott V.>

Odd Lighting Question revised (sorry guys and gals), SW fixture choices, reefs...  9/25/08 Hello crew, hope you all are well. <I am here, thank you.> So I have a lighting question for you. I have a 60 cube that is 30" long x 24" tall x 18" wide. I was using two t5 lighting units, both 48 watts. I recently upgraded to a SunPod 30". Its a 150 watt MH with all the LED's ( very happy to have those for night time viewing). I took the t5's down, but after chatting with some reefer friends that use other types of lights with there MH's, I started to think about maybe using the t5's with the MH SunPod. Would you recommend this? <You could, its up to you. Most use T5 actinics with MH to 'blue' the water a bit more and make the livestock fluoresce a bit. Realize that all light transfers some heat to the tank, even T5s.>br>I am not doing any sps, just softies, LPSs, polyps, and Shrooms. Also, I have read/heard never to remove the center plastic beam on the top of the tank, and I haven't, but it casts a shadow in the center of the tank from the MH. What's your take on that black plastic beam? <I hate the danged things, but if your tank was designed with it leave it be.> I am hanging the MH pendant about 10" above the tank, do you think I should lower it? <7-10' is about right.> Also because my tank is so tall would I benefit from lowering the light, as well as using the t5's? <What you list will be fine with the light you have, but the T5s will not hurt anything either. They can have quite an impact on the look of the tank depending on bulb choice.>br>Also, given the right conditions how long does it usually take coal to grow/propagate? <Depends on the coral.> II have notices some of my zoo's grow new polyps, but my hammer hasn't gotten any bigger or shown any signs of new growth. I also have never had Mushroom reproduce either. I have heard stories of people putting mushrooms in a tank and two weeks later splitting occurs. All my water parameters are in line and I test and change water religiously. I feed the coral with DTS 3 times a week. Any suggestions? <Mushrooms do appreciate more of an indirect, subdued light and current. These are one of those corals that can grow like gangbusters in ill maintained systems and just be there in immaculate tanks. More info at the link below and linked pages above on the page.>br> http://www.wetwebmedia.com/corallim.htm Thanks again guys and thanks for your continued support and information. This site has been a wealth of information for me over the past year. <Heee, thank you and welcome!> Spencer Hall <Scott V.>

Lighting.... again. 9/5/08 Hello, friends! <Hey there Thomas.> Sorry I do not have the prior emails to accompany this, I'm using a web based email at this time. <It is a world of difference sometimes.> The long and short was that I am setting up a reef tank 36" long and 24" deep (top to bottom). The tank is a 65 gallon tank. I do plan to keep softies and stonies as I read more about them. I've exchanged emails with a crew member there, and had initially decided on an 8 bulb T5HO fixture for this tank. One thing he mentioned that has me hesitant, is that they won't produce that 'shimmer' that is so amazing in nicely done reef tanks. <Nope, not like the MH will.> I've read your FAQ on medium system metal halide lighting, and I've looked at several fixtures... none really match my setup in the FAQ. The fixture I'm looking at has dual 175w halides with two 65w CF bulbs. I need to go with two bulbs due to the center brace. <I love these tanks, but the center brace is a pain.> Think this is adequate for lighting? <Oh yes, you will have quite a bit of overlap in the middle of the tank, suitable for your higher light needing corals.> There is a unit that has dual 250w halides, but I'm thinking that may be a bit excessive. <This can work too, but will be quite a bit of light and heat to manage with this spread.> The T5HO is still an option, I'm just fascinated by that shimmer.... <I hear you, I fought it for years. Recently I have finally given in and honestly would never go back. I just personally like the T5. Others have tried the same and go back to halides. If you are the type that does not mind a slightly higher power bill along with a chiller, then IMO it really does come down to the shimmer. Do you want it or not? I used to think I could not live without'¦now it is no problem.> Best regards! Thomas <I hope this helps you decide. For what it is worth, the LED lighting is quickly advancing and will likely be the standard within the next few years. At the moment it is expensive, but LEDs do combine the advantages: low heat of T5 with the shimmer much like the MH, a lower power cost of either, no bulb replacement, along with some amazing adjustability in the current units out there. Something to consider/watch out for in the next few years. Cheers, Scott V.>

T5 or Metal Halide 9/2/08 I need to make a very big decision regarding my 120 gallon reef to be Tank. I have been looking at the following fixtures: current USA's Nova Extreme 8x54, and the Outer Orbit 175w 10,000k combination halide/actinic fixture. I do not yet know exactly what I want to keep for corals, clams, etc. in this tank. I do know that I would like to have the greatest flexibility as to what I am able to keep/grow in this tank. I really do not want to have to deal with the light problems of 250 W halide, so another question is would 175 W halide x 2 be sufficient? <Yes, for the most part you could keep what you like with the correct placement in the tank.> The Nova Extreme is a 432 W fixture, while a Outer Orbit is a 516 W fixture with all lights on. What would I lose in my ability to keep SPS corals and clams by going with the T5 fixture? <No, you can keep SPS and clams just fine with the T5, again with appropriate placement; higher light hungry corals closer to the top.> Setting SPS and clams aside, how good would the lighting be for most other corals? <Very good in general.> I would really appreciate some advice as to what fixture would be best for me to go with. <Either fixture can fit the bill for what it sounds like you want to do. I have personally become partial to the T5's in the recent months, see first hand what these fixtures can do. The T5's will transfer less heat to your tank, an important factor if you are borderline on needing a chiller. Also, the bulbs are easy to switch around and swap out to get the look one wants. The MH are tried and true coral growers. The big thing that keeps many from leaving the MH is the shimmer they provide, you just don't get that with the T5's. You will just have to decide what is important to you.> Best regards, and thanks greatly for your help, Jeffrey C <Welcome, have fun setting this up, Scott V.> Lights question, reading...   08/28/08 Hi :-) Can you please tell me the difference between the following lights? 1. PC - Power Compact 2. CFL - Compact Florescent 3. PL - I don't know what the full form is for this one. <... this last is a company: http://www.pllight.com/about.php> Is PL good enough for LPS and Zoanthid and Shrooms in a 40cm water column tank? Thanks Again Ranjith <Read here: http://wetwebmedia.com/marsetupindex2.htm the last couple trays... and Corallimorph Systems FAQs... Don't write... read. BobF>

Re: Lights question   8/29/08 Aloha bob I have gone through the FAQs many times. My question is I don't understand the difference between these technologies. Couldn't get out of Google or Wikipedia too. <? What do you mean by "couldn't get out?"> I apologise for not being clear with the question though. Will zoas shrooms and a moon coral thrive in a cfl lit tank of 16 inch water column depth when lights are 6 odd inches away from the water level? <Yes, can> So many say MH is needed and so many say otherwise. Driving me nuts. I see you recommend full spectrum T12s. <I have at times, places... There's a bit more to any given "equation" of determining a "good fit" for lighting (and other gear)... To wit: what are your intents (not needs)... IF you're trying to maximize growth, reproduction, repair from fragmenting... MH is very likely a/the route to go... perhaps with even some "natural" light... But, if you simply want to keep these sorts of Cnidarians "successfully", less photonic energy is fine, preferable in terms of not "over-driving" other factors (e.g. temperature, biomineral content...) and increasing the cost of operation of your system> I just do not want to go to MH unless necessary due to the heat issue. Cheers Ranjith <I understand, and agree. Bob Fenner>

Lighting questions... SW, gen.  07/23/2008 Hi, <<Hello, Andrew today>> There are many hang on lighting systems available in the market these days. <<yes>> They combine MH and tube lights/PC/CFL lights in the same canopy. The distance of bulbs from the water surface to be effective for MH is much higher than the tubes and PCs etc. <<Yes, this is mainly due to heat transfer from light. Too much heat at the water surface greatly increases evapouration>> Which means the lights will either be too bright or too inefficient based on how high or low one chooses to set them at. <<The average for Metal halides is about 8 inches. This provides a good chance for heat dissipation into the air, lowering evap and allows for the largest portion of usable light into the tank>> The question is, is it efficient to combine different light sources in the same canopy? <<yes, I don't see any reason why not. However, for me personally, I really don't see a need to combine metal halides and T5, for example, as the white marine light will mainly come from the halides>> PS: I almost forgot, some of them also advertise they have moonlight LEDs in the same canopy :-) <<Moonlight...hmm....Unless your very very specific on creating the moon phases in the aquarium, then, then the only purpose is so you can view the tank after lights out, when its dark>> Cheers, Ranjith <<Thanks for the question, hope this helps. A Nixon>>

Re: Lighting question 07/23/2008 Hi Andrew, <<Hi>> I think I confused you. <<Slightly>> I understand all the reasons for the difference in distance from water level for MH and other lights. Look at it this way If you keep a T5 or Compact Florescent at 8-10 inches above water level, will you not lose the major part of the effectiveness? On the other hand, you NEED to keep the MH at the same 8-10 inches from the water level. <<I mentioned keeping a halide unit that amount above the water level, not a T5 or compact fluor unit. These are usually about 3 inches above water level. Yes, if you had that at the 8 - 10 inches height, yes, you would certainly loose the effectiveness of that type of lighting unit>> So, if a single canopy has both types, then what height to keep at? <<If you referring to a canopy which has halides, then 8 inches. This is where I don't see the need to mix a canopy of halides and T5/PC lighting, as the effectiveness of the tube lighting is far less effective>> Cheers Ranjith <<Thanks, A Nixon>> Re: Lighting question 07/23/2008 Thanks a Lot Andrew. That sentence of "effectiveness of the tube lighting is far less effective" is what I wanted to hear from you guys :)) I was thinking of buying something like this http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+3733+12779&pcatid=12779 They basically have T5+HQI+Led all on the same system. I was wondering if this is useful. I guess it is ONLY fine if u want to Use one type as a full time light and others as an pure viewing pleasure right? <<the above link shows "page no longer available". However, yes, that type of lighting fixture is fine. Was just looking at the Outer Orbit HQI/Compact Fluorescent/Lunar Fixture>> Cheers Ranjith <<Thanks, and have a good day. A Nixon>>

T5 vs. Metal Halides 6/28/08 I first want to say what a wonderful site and thank you for all the help you have been so far. <Great, glad the site has been of help, thank you!!> My question is about the debate over T5 and MH. <Can be a quandary.> I have a 300 gallon 96L X 24W X 30H. I am currently running 4-250 watt MH and was wondering if two Tek 48" 8 bulb 54-watt fixtures would be a better choice. Everyone I talk to is worried about the 30" depth will this be a problem with T5. <Neither is the 250W MH depending on bulb choice and what you put near the bottom. It is all about placement.> I am planning on keeping all sorts of LPS, SPS, Clams, Mushrooms, etc. . I know the corals that need the most lighting will need to be placed at the top but will the 16-54 watt T5 be enough. <I feel it is. With any light the placement comes into play, but you will have similar lighting with these T5 fixtures as you have now.> My main issue with the MH is heat and electricity, I know I will lose the shimmer but will I also loose the heat and electricity? <Yes, to some extent. Don't expect an earth shattering difference in you power bill. The halides you run now consume 1000 watts (likely about 1200W in reality, depending on bulb and ballast), while the T5's you propose will pull very close to what they are rated, Thanks for a wonderful site, 864 in this case. This does definitely add up over time, but you have to consider that you already own the MH's!! As for the cooling, the bulb's heat is spread through the bulb in either case, the T5's just spread it over a longer area. This does translate into less heat your tank will absorb, especially with fans running between the bulbs and water. The other factor is cost of replacing the bulbs. The T5 bulbs should last a bit longer than the MH, giving a slight edge to them here (this again depends highly on what bulbs you do use). I must say I am a huge proponent for the T5's, but do not use them due to my addiction to the shimmer!> Brad <I hopes this helps you decide, Scott V.>

A quick thank you! 05/29/2008 Hello, I wanted to send a thank you for answering my lighting question. I really appreciate all of the hard work undertaken by the WWM crew. My ability to care for our tank in a responsible and informed manner has greatly improved since finding this website. The families, teachers, and foster grandparent volunteers at my workplace, a non-profit child care center with 160 children ages 6 weeks through 6 years, enjoy a thriving, beautiful tank each day. With regard to my lighting question, I decided to go ahead and change the tank lighting to T5 lighting, as per my question. was promptly answered by A. Nixon on 04/05/08. We ordered the lighting through one of the advertisers on the WWM website, marine and reef. The fixture was $200 less than what my LFS was offering and included free shipping. We ordered it on a Monday, they verified the shipping address on Tuesday, shipped it on Wednesday, and it arrived on Friday! It is now all set up and doing well. We have noticed things we never noticed before, sponges and brittle sea stars etc., because we couldn't see in the darker rock crevices. We love the new lights and thank you again for your advice. Sincerely, Kim <<Its my pleasure Kim, I am really glad to hear everything is well and new aspects of viewing pleasure are now being explored. Kind Regards, A Nixon>>

Light Conversation (Lighting Upgrades)  5/29/08 I have a 90 gal glass tank, 48x24Dx18. It's been setup for about 3 months. 100 lbs live rock, sand bottom, wet dry filter, 25w Aqua UV light. Reef Devil protein skimmer, MRC CR1 calcium reactor and a 1/4 hp Oceanic chiller. Live stock consists of 3 Blue/Green Chromis, 2 False Percula Clowns, 1 Firefish, 1 Yellow Tang, 1 Blond Naso Tang, 1 Exquisite Wrasse, 1 Flame Angel, 1 Coral Banded Shrimp, 1 Red Serpent Star, and 50 Hermit Crabs. <A nice mix of fishes, but we need to rethink the Naso Tang. This fish requires a very large aquarium (hundreds of gallons) in order to live anything close to a natural life span, and really needs to be given away to an aquarist who has the facilities to keep this fish for the long run. Just a gentle reminder! Scott F., your conscience, in today..> Corals consist of 1 Open Brain, 1 Frogspawn, 1 Trumpet Coral, 1 Moon Brain, 3 small Ricordea and a small assortment of Mushroom corals. Water movement is accomplished with 2 Maxijet 1200's with mod kits along with the return line run from a Dart pump. Currently my lighting is 4- 96w pc's, 2 10k and 2 actinic mounted in a closed hood about 7" off the surface of the water with 2- 3" fans, 1 pulling and 1 pushing. I would like to upgrade my lighting. <A good idea. This selection of corals will benefit from greater intensity> I can fit 6- T5's 54w HO run off of 3 Accu-start ballasts with various selections of bulbs or I can also go with 2- 250w MH, either Ushio 10k or Radium 20k run off of 2 Ice Cap electronic ballasts along with 2 VHO actinic T5's into the existing hood. My goal if reasonable is to add stony corals and maybe a clam to the current stock. Any suggestions and opinions would be appreciated. Thanks, Roger <Well, Roger, I'd suggest the T-5s, with a mix of daylight-flavored bulbs, such as the Giesemann "11,000K", or UV lighting 10,000k bulbs. If you go the halide route, I'd recommend some double ended pendants, such as Sunlight Supply's "Lumenmax" units in 250 watt configuration, with either a Phoenix 14,000k bulb or an AquaMedic 10,000k bulb. Although arguably less energy efficient than T5's the double ended halides in well-designed reflectors are always a fine choice, and will provide excellent intensity for a wide variety of animals. Don't forget to gradually acclimate your corals to either of these higher-intensity light sources, as you don't want to burn them as he new light system is breaking in. Hope this helps! Regards, Scott F.> Fixture Size 5/15/08 Hello Bob {and crew}, <Hello, Scott V. with you.> I have a quick question....I'm currently setting up a 75 gallon reef tank and I have run into a slight problem with my lighting. The canopy I am going to use fits snug to the top of my tank {like normal canopies do...lol}, so this prevents me from using a 48" fixture. AARGH. <I here you, frustrating. Do realize that many of the T5 fixtures actually measure in at 47-47.5' . This is one of the advantages of T5's, they were developed to fit inside canopies!> I plan on using T5's {most versatile for easy corals/invertebrates I plan to keep} - subject to change per your advice/my further research! <T5 is a fine choice.> My question is, do you see a problem with me utilizing a 36" fixture{s} or something other than the 48" fixture? <No, although your tank will be a bit darker on the ends, you will need to place livestock accordingly.> How about placement of a shorter fixture? <Likely in the middle, you could put it to one side if you like the look (it will leave the other end dark).> I'm trying to stay away from the cliché of a normal wattage per gallon, having said that, what's a good ratio for beginner corals and inverts? 3-4...lol? <Of course this depends entirely on what you wish to keep, but 4 watts per will serve you for what most consider beginner corals.> Your advice and instruction on what I should do is greatly appreciated. Thanks for your time in helping us less informed! Jay <Welcome, have fun with the new tank! Scott V.>

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