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FAQs about Lighting SPS Corals

Related Articles: SPS Corals, Acroporid Corals, Dyed Corals,

Related FAQs: SPS 1, SPS Identification, SPS Behavior, SPS Compatibility, SPS Selection, SPS Systems, SPS Feeding, SPS Disease, SPS Reproduction, Acroporid Corals, Agariciid Corals, Astrocoeniid Corals, Merulinid Corals, Pectiniid Corals, Pocilloporid Corals, Siderastreid Corals, Stony Coral Behavior, Coral System Set-Up, Coral System Lighting, Stony Coral Identification, Stony Coral Selection, Coral Placement, Foods/Feeding/Nutrition, Disease/Health, Propagation, Growing Reef Corals, Stony Coral Behavior,

Small Marine Aquariums
Book 1: Invertebrates, Algae
New Print and eBook on Amazon:
by Robert (Bob) Fenner
Small Marine Aquariums
ook 2: Fishes
New Print and eBook on Amazon: by Robert (Bob) Fenner
Small Marine Aquariums Book 3: Systems
New Print and eBook on Amazon:
by Robert (Bob) Fenner

Led lights; effect/s on stony corals      1/1/15
This may be a strange question. I have 140 reef set up lots of Lps and some sps. I was running vertex illuminlux led lights and recently switch to 2 Kessil 360w lights. The color to my eye is a little different but I have probably 5x more shimmery then before. My corals seem much happier now. My question is: Have the corals improved due to more shimmer or is it only dependent the spectrum of light???
<It will/would take a few weeks for the corals to change... so my guess the difference is primarily the lighting. Bob Fenner>

JBJ "Next Generation" 24 ga LED Nano Cube ok for SPS?      2/9/14
Hello crew. JBJ has come out with a new(ish) 25 gallon LED Nano Cube with Cree emitters. What I can't seem to learn is whether this tank would work with light demanding SPS corals and clams.
Would someone there know the answer to this question?
<Likely all of us do... Are you familiar w/ WWM? Using the indices, search tool (on every page)? Bob Fenner>
Thanks, Steve
re: JBJ "Next Generation" 24 ga LED Nano Cube ok for SPS?

I had already searched via the search tool before I sent in my question.
The problem is that I got many false hits, as this product is fairly new.
I did find information elsewhere (finally) about PAR. I do not think PAR is satisfactory for SPS. Maybe James G. could weigh in.
<Will Bcc him here... A more substantive (useful) reply would have been to search re PAR, PUR and secure a test device.
Many clubs and quite a few LFSs have such for loan. This is really the only reliable way to determine suitability; other than bioassays with actual livestock. BobF>
Re: JBJ "Next Generation" 24 ga LED Nano Cube ok for SPS?

Hi Bob,
I will be happy to take care of this tomorrow, late morning.  Thanks.
<Thanks James. B>
Re: Fw: JBJ "Next Generation" 24 ga LED Nano Cube ok for SPS?      2/10/14

Hello Steve,
Bob has asked me to chime in my two cents in regards to your query. PAR can be a deceiving measurement of light for our needs as far as growing corals. Corals only use light in the range of 400-550 and 620-700 nanometers. If we take a 400 watt metal halide and measure PAR, it may well exceed 400. But the metal halide lamp will produce light in the spectrum corals do not require so how much of that PAR is available in the above spectrum. Well designed lamps will try and get as much light as possible in the above spectrum. This is why many people believe that a PAR of 200-300 measured on LEDs is not good enough but if the spectrum is fine tuned to the ranges stated above, then that would be equivalent to say a PAR of 400-600 on a metal halide lamp because the PAR reading is generated by measuring the light only in the spectrum corals require.
Having said that, it is very important to look at a spectrograph of the light produced by a given lamp or LED fixture to ensure the light being emitted is very close to the above stated range.
James (Salty Dog)
Re: Fw: JBJ "Next Generation" 24 ga LED Nano Cube ok for SPS?      2/11/14

Thank you very much, James. I am a skeptical of a manufacturer who does not
provide a spectrograph. I will inquire further from the manufacturer.
Re: Fw: JBJ "Next Generation" 24 ga LED Nano Cube ok for SPS?      2/11/14
You're welcome Steve.  James (Salty Dog)

switching from 250 w to 400 w MH   1/27/14
hello again Mr. F,
Everything is going well with the tank, so it is time for my next move in order to achieve " SPS nirvana " : I currently have a  180 cm AquaMedic fixture over my 2.1 meters long / 70 cm wide / 70 cm deep  tank with 2  x 250 w MH bulbs in some very small reflectors
<I would change these before, way ahead of upgrading the lamps to higher wattage>
and 4 x  80 w T5. The fixture is too short, and the MH bulbs are too far away from the ends of the unit to get coverage on the sides of the tank.
I measure 180-200 max PAR just under the bulbs 25 cm deep into the water columns and this numbers are low for my Acroporas. And the corals look dark and like they would need more light.
So I was thinking to install 3 x 400 w MH bulbs in LumenBrite reflectors with CoralVue Ballasts. What do you think?
<Better by far; but mainly the reflectors>
 And more important : how will I do the acclimation in order not to burn the corals already used to low light.
<Read here re: http://www.wetwebmedia.com/acclimcoralslight.htm
Or should I consider 2 pieces of  8 x 54 w 900 cm long ATI T5 fixtures that are dimmable and I could start at lower intensities and slowly bring them up?
thank you,
<Up to you... the extra intensity (of light), but principally the better reflectance, coverage will be an improvement. Will it be worth the cost of changing out the fixture, electricity? Bob Fenner>
Re: switching from 250 w to 400 w MH      1/28/14

Thank you for your answer, but I need some clarification: you stated that you would change my current fixture before upgrading to higher wattage. What dose that means, I should get 4 x 250 w in LumenBrite reflectors and at some point after that I should get 400 w?
<Ah yes... IF I had the funds, desire to change but one aspect, I would get the reflectors first>
Or do you think I should go directly to 400 w which in my opinion should be the safest way to keep a full sps tank of mine dimensions. Electricity bill and price of fixture is not an issue, I have invested too much money, time and energy in this tank to stop now , I just want the best conditions for corals.
<Mmm, well...>
I know that if I go directly to 400 w the transition would be very difficult and dangerous for my corals,  but so was the installation of the 300 l RDSB with Chaetomorpha that now I am glad I did it.
<Ah yes>
Thank you,
<Welcome. Bob> 

LED lighting and Acropora/Reef Lighting 2/25/13
Hello gang.
<Hello Larry>
I bought a Kessil 90 watt fixture the other day to use over metal halides.
The tank is a 29 gallon and I have a few Acropora in there.  I don't know why the polyps are half way out.  Perhaps it's too much or too little light?
<Is likely the change of spectrum and/or an increase in intensity.  Corals should always be acclimated to different lighting technologies.  Please read here.
I've never had LEDs before.  The tank is relatively new, all of the water parameters are fine except for the nitrate is at 5.0 and the KH is around 5.0.
<I would try to get the nitrate down to about 1-2ppm.>
I've noticed the KH on another tank of mine was high in the beginning but came down through time.  I think the reason is that I bought Florida base rock, which is not the live rock that is typically sold for reef aquariums.
This base rock is dry, chalky and white.  Would a KH of 5.0 be harmful to Acropora?
<dKH is a measure of buffers present in seawater and buffers are mostly made up of carbonates which the corals need to build their skeleton.  Without the presence of carbonates, corals cannot grow or build their skeletons.
I would keep your dKH higher than this.  A minimum of 7dKH and a maximum of 12 should work very well.  It's best to monitor the dKH on a weekly basis, especially if there are many SPS/LPS corals present in the system.>
I also have some Zoanthids, Halimeda plant and a gorgonian.
Thank You
<You're welcome.  James (Salty Dog)>
L. Splitter
Re LED lighting and Acropora/Reef Lighting 2/25/13

Thanks James. 
<You're welcome.>
I had meant to say that the alkalinity was around 5.0 not the KH.  Would this still be too high for a wild Acropora specimen?
<What kit are you using to measure alkalinity?  Are you measuring meq/l? 
If you are, and I believe you are, you then multiply the meq/l reading by 2.8 to give you dKH.  In your case it is 14dKH, a bit on the high side but not harmful to Acropora or other stony corals.  Do not dose any buffers in the system until the level drops to around 8 or 9 dKH.>
<You're welcome.  James (Salty Dog)>
Re LED lighting and Acropora/Reef Lighting    2/27/13

Thanks James
<You're welcome.>
The test kit is made by Salifert and the units are in meq/l.
<I assumed that was the case.  Just multiply your results by 2.8 to get the dKH value.>
What products would you recommend for a 29 gallon reef tank?
<Mmm, why just a 29 gallon tank?>
There are quite a few to choose from.  In the past I've used the buffer and calcium additions from ESV (as well as iodide, magnesium and boron) and two little fishies.  I've used Kent products for trace elements and coral vite.  I also use RO/DI water and use a protein
<The products I like most are:
Brightwell Calcion-P for calcium
Seachem Reef Buffer
Seachem Reef Builder
Tropic Marin Bio-Strontium
Tropic Marin Reef Actif  (NO3/PO4 reducer and also provides food for the corals).  This product works better than
most any other NO3/PO4 reducer I have used in the past and need only be dosed weekly.  Does a great job clarifying the water as well.
For coral maintenance I am using the Red Sea Foundation products but when they are gone I will not use them anymore, too darn many things to dose on a daily basis and very expensive to buy all the components.  I've been hearing very good reports on a AquaVitro Fuel which is an all in one additive for corals (excluding food).  This is the product I am going to try. AquaVitro is a subsidiary company of Seachem. 
thanks again
<You're welcome.  James (Salty Dog)>
Re LED lighting and Acropora/Reef Lighting 2/28/13

Thanks again. 
<You're welcome.>
The reason I have a 29 gallon is that it fits in my office pretty nice.
<I did not mean for my statement to come across like that.  Was just that the products would work just as well in any size tank.>
 One other thing is that I had put some bleached coral in my tank that was left over from another tank.  In that tank there was copper, but this piece of coral had been left dry for about 4 years.  There wouldn't be any copper left on this piece of coral would there?
<May be some residual but likely not enough to cause any problems.  Bob may comment here if necessary.
James (Salty Dog)><<Not a worry; as James says, very little Cu here. RMF>>

Lighting Change, for SPS  – 12/03/12
Dear Crew,
So, its getting to be that time of year again when I start to think about improving my reef tank drastically. I have arrived at the idea that I want to try some different types of plating corals, and branching too. Of course
I realize that this means SPS. I also know that there is no way my current four 65watt pc's will be enough to keep them. (two 6500k, and two 10k) I don't want to go to metal halide at this time, but instead would like to go with T5. I found a six 54 watt bulb fixture which I fancy. Firstly, would this be progresses or regress in the direction I wish to go?
<Nominal, a few tens of percent forward>
 Secondly, assuming it is progress which may be a jump in and of itself; what combination of bulbs would you recommend? I was thinking: 2 Coral Plus (
and 4 Midday Sun (
<These would be fine>
I likely would want to try some plating Monti's, Birds Nest, Pocillopora, and of course Staghorns. Now, assuming that the purchase would be regress;
would it be better to save my money and buy a metal halide later?
<For your size system... Mmm, no; I'd save and jump to LEDs. For (much)
larger systems, an intermediate choice at this time might well be MHs>
 I apologize if this message was slightly unorganized, but I felt that it was
best to send you the links to the exact bulbs.
<No worries. Bob Fenner>
Re: Lighting Change, /SPS  12/3/12

<Big B>
If then, this wouldn't actually be what I consider measurable progress, and instead you recommend LEDs I have a few questions. Firstly, if I have a basic understanding of PAR then, PAR of 100 is natural sunlight correct?
<Mmm, a bit more involved than this...>
This is unrelated at this time but relates to the next question:
This is advertised to have a PAR of 38. Which is significantly lower than 100, am I looking at the wrong type of bulb or would this be sufficient?
<How to put this? One needs, wants to have the registration/measure of 100 PAR or more "at the site" of the coral/s themselves... so you need to start w/ more at the surface total>
The high light Acros would be within 8 inches of the surface. I am assuming that multiples would have to be purchased, but what number would be appropriate for a standard 55 gal LPS, SPS reef? What distancing is best for this type of lighting?
<Have you seen James articles re LEDs on WWM? Am referring you to him here.
Re: Lighting Change, /SPS /JamesG    12/4/12
<<Hello Bryce.  Bob asked me to give my input on your lighting query.  I will clear up your understanding of the PAR 38 lamp.  In this case, PAR 38 has nothing to do with actual PAR (Photosynthetic Available Radiation). 
Instead it means "Pressed Glass Aluminized Reflector" or "Parabolic Aluminized Reflector" depending on who you ask.  I prefer the later.  The 38 means eights of an inch just like T5 where the 5 means 5/8" of an inch. 
In the PAR 38 lamp it means the lamp measures 38 eights of an inch or 4 3/4" in diameter.  There are also various sizes and styles of "PAR" lamps.>>
<Big B>
If then, this wouldn't actually be what I consider measurable progress, and instead you recommend LEDs I have a few questions. Firstly, if I have a basic understanding of PAR then, PAR of 100 is natural sunlight correct?
<Mmm, a bit more involved than this...>
<<PAR and CRI is not to be confused.  Natural sunlight has a Color Rendering Index of typically 100.>>
This is unrelated at this time but relates to the next question:
This is advertised to have a PAR of 38. Which is significantly lower than 100, am I looking at the wrong type of bulb or would this be sufficient?
<How to put this? One needs, wants to have the registration/measure of 100 PAR or more "at the site" of the coral/s themselves... so you need to start w/ more at the surface total>
The high light Acros would be within 8 inches of the surface. I am assuming that multiples would have to be purchased, but what number would be appropriate for a standard 55 gal LPS, SPS reef? What distancing is best for this type of lighting?
<<This will depend on the types of corals that will be kept.  If SPS, than I would recommend a minimum of three of the "PAR 38 LED Lamps".  For the cost of those you would be much better off with a LED Pendant which will put out much more PAR and have a spectral curve closer to the PUR range.  You may want to read a couple of articles I wrote a
while back to help you better understand PAR/PUR and spectral wavelengths. 
These links will take you to them.
James (Salty Dog)>>
>Thank you James. B<

Breeding Cardinals, SPS    9/15/12
Dear Crew (Bob F.),
About a year ago I acquired four Banggai Cardinals. They have grown considerably, and I would like to look at the possibility of breeding them, help relieve pressure on nature a bit. Anyway, I feed them Mysid, and cut up shrimp pieces daily, I also have set up a 6 gallon refugium. What are some other tips you would have for encouraging breeding behavior?
<Read here: http://wetwebmedia.com/banggairepro.htm
and the linked files above>
I was thinking of adding squid meat to their diet. They are currently being kept in a reef tank, LPS corals, two Firefish Gobies, 1 Tri-color Wrasse, 2 Thor sp. Shrimp, 1 Yellow Watchman Goby. Water Parameters: NH3-0, NO2-0, NO3-5ppm, Ca-420, pH-8.3, KH-10. The tank is 55 gallons. On a side note, I have another 55 gallon, and I would like to keep/breed via asexual fission a BTA.
<Can be done... read, search on WWM re Entacmaea>
I currently have four 65 watt power compacts above the tank. The lamps are 2 6500 and 2 10k. Should I look into maybe adding a 75 watt Metal Halide?
<I wouldn't... too much electrical cost and heat for the intended benefit>
Would the anemone be doomed without it, or split without it?
<I would cut the anemone (through the siphonoglyphs/mouth...>
I know you don't recommend anemone purchasing, so I also have been looking and found some "low light Pavona Corals, and a "moderate light" Acropora, and Montipora. Is this even possible because I am skeptical, as I have always heard these are high light corals.
<Would have to know what whomever means by "moderate">

I would like to look into getting some SPS at some point in time, but I don't want to be a fool falling for a scheme. Thanks!
<Welcome. BobF>
Re: Lighting Acropora     9/15/12

Dear Bob F,
   The "moderate" light requiring Acropora is from Foster and Smith. Here is a link:
Is this something you would consider with 260 watts of PC lighting over a standard 55?(2 65 10k & 2 65 6500) Or, pass and wait for a lighting upgrade?
<Mmm, well, you/one could keep most members of the genus in such a system, w/ this lighting... if the colonies were placed "up high" on rock, w/in a few inches of the surface. Much has to do w/ the reflectors chosen/used for the lighting, and desire for rapid, colorful, optimized growth. Bob

Lighting for SPS 9/1/12
Dear WWM,
<Hello Bryce>
I recently sent in an email about a pending nano system I would like to set up for frags. It was suggested to me that I use a Ecoxotic PAR38 LED Aquarium Lamp to light the system. I was wondering if this would still apply for trying an Acropora frag, or perhaps a Birds Nest coral. I am also wondering if this type of lighting would be adequate  for anemones.
I wont mix SPS and anemones, but I would like to at least have an idea of whether or not this is a multipurpose light or not really.
<In my opinion, this LED lamp is more suited for highlighting areas in a tank.  It also has a very sharp narrow focus due to the 40 degree lenses used.  This would not be my choice for your needs.   Have you looked at the Orphek PR25?  This LED lamp has more LEDs and the spectrum is tuned for coral and anemone growth.  This LED lamp uses 60 degree honeycomb
reflectors and provides  12" x 12" coverage with the lamp suspended 12" above the water line.  Take a look here.
Orphek's contact email is sales-3@orphek.com>
<You're welcome.  James (Salty Dog)>

Red sea max 130D lighting question, for SPS
Hello WWM crew,
<Hi Mike, Misty here>
I had one question for you, My red sea max 130d has 2x55w "compact" t-5's stock lighting. I believe both bulbs are half antic half 10000K. Their website claims this tank can handle all softies, LPS, and even some SPS corals.
What's your thoughts on that? if it can then I am guessing placement of corals has to be high for LPS and SPS.
<Based on the old standard of 3w/gallon, I' say that the 110w is sufficient, especially for the softies and LPS. I'd really only worry about placing the SPS higher. I haven't had T-5's, but started nine years ago with only PCs and had great luck with softies and LPS (wasn't brave enough for SPS back then). That being said, it's really about the depth of the tank as well...so I'm guessing from what I've been able to find that your tank is 32" high (deep). Not sure what kind of sand bed you have, etc. So with a 32" depth, I'd definitely put the SPS at the higher points on the rock...but heck, with 500w of MH and another 110 of
PC's in my tank, I do the same thing (24" deep with a 5" DSB). Actually more important here for your SPS might be flow...plenty of laminar flow is very important to SPS. I've had SPS frags grow on the sandbed just fine with enough flow...and crappy up higher with less flow. Flow seems to become more and more important as my experience grows...as a diver, I can speak first-hand about currents and the health of a reef. Basically, start slow, as any good reef should. Take time to pay attention to new frags/colonies and see if they are doing well in the environment that you are providing. If not, move them to higher/lower light and higher/lower flow. Just don't dally should something take a turn for the worse. Takes
a while for things to grow...less than 24 hours for them to die.>
<Cheers, Misty>

SPS Lighting/Growing Corals 9/14/10
<Hello Marc>
I am a made keen WetWebMedia fan and I regularly browse your site for answers and guidance so first off can I say a big thank you.
<You're welcome.>
But today I need some help please. I have a 1100 litre tank which I have been running now for a year with mainly SPS corals but I have struggled with coral health (there are only two fish in the tank). Nothing is dying but I am not getting the growth and coloration I was hoping. I have gone down the path of heavy
skimming, low nutrient (low Phosphate and Nitrate - essentially undetectable)
<Is better to have some nutrients present.>
and very regular water changes. This together with reasonably intense 14k 250 watt metal halide lighting.
I am beginning to wonder if the intense light is causing some photo inhibition in my corals (I getting very pale SPS - similar to what you see in ZEOvit tanks) and slow growth. Is the low nutrients together with
intense lighting causing me problems.
<The low nutrients may.>
Other observations are almost no (to none)
coralline algae in the tank.
<Supplementing your MH lamps with actinic lighting will help coraline growth.>
Other parameters are
Alk 8 - 9 dKH
Calcium 400 - 450 ppm
Magnesium 1250 - 1350 ppm
Strontium, Potassium Iodine all within NSW ranges (tested by a lab)
Salinity 1.025 - 1.026
pH 8.15 - 8.35
I do not run a refugium but the last time I tried to grow macro algae it just failed to take. I hope you can give me some ideas.
<Some nutrients in the water are needed for growing macro algae. Perhaps your system
is too sterile.>
At this stage I am considering less intense lighting and maybe looking at feeding but I don't know what. There are so many products out there such as amino acids, coal snow etc etc.
<Your lighting shouldn't be a problem, and as for feeding, most SPS corals do not consume phytoplankton but do just fine growing on photosynthesis alone. I believe reading the following will help you.
<You're welcome. James (Salty Dog)>

No Light Getting To Base of My Acropora -- 07/20/10
<<Hey Daniel>>
I have a branching Acropora and it has been growing well for the last 16months now it is a small mini colony. The base doesn't get much light now that the top parts are covering it up.
<<This is not uncommon to captive systems -- no 'arc of the sun' to illuminate all sides'¦ Along with a likely absence of reflective surfaces such as Aragonite sand that has been 'scoured bright' by wave action/an abundance of associated biota>>
The polyps at the base do not expand and the tissue is starting to peel off. Is there any way to stop this?
<<You can try positioning the colony where more light will be 'reflected up' from your substrate (if a possibility). Or probably more to your dislike -- you can thin out the branches somewhat to allow more light to penetrate'¦much like pruning a fruit tree to increase its production. I must mention'¦ In my experience such 'light deprived' tissue will usually just lose color and maybe diminish/recede somewhat, but generally does not 'peel' unless there are other issues. You may also need to increase water flow around this coral>>
Daniel Naveen
<<Cheers'¦ Eric Russell>>

Re: No Light Getting To Base of My Acropora -- 07/25/10
<<Hello Daniel>>
I've attached a pic of the Acro.
<<I see them--thank you for these>>
You can see how the parts that don't receive light are going pale and the polyps don't extend either,
<<Indeed--and my response remains the same--with perhaps the addition of an increase in water flow>>
this pic was taken after lights out. The other picture shows how the branches on top look with my lights on.
Daniel Naveen
<<Cheers'¦ EricR>>

Solid state lighting experiences? Question? -- 06/10/10
Dear Crew,
Just wondering if any of you have experience of growing SPS corals under solid state LED lighting?
<None personally, but have studied, seen enough to make a resp.>
I currently have two T5 tubes (25W, one marine white one marine blue/actinic) and an array of four reef white LED Aquarays (containing both white and blue diodes) over my 66 US gallon (248l) tank. Currently the tank contains soft corals such as a large Sarcophyton near the top and numerous Zoanthid colonies lower down in the tank, all of which are doing very well, however the time has come to give in to my desire to attempt SPS corals (again - first attempt not successful and deemed that I was too inexperienced so concentrated on soft corals etc first).
<A good process, order>
Am aware of the intense lighting many of these creature require so want to make absolutely sure they receive the correct illumination to thrive and look their best BEFORE getting them - my planned stock (i.e. wish list) are: Acropora species, plating Montipora, Seriatopora, Pocillopora and (if I'm very lucky) one of the smaller clam species. Am happy with the flow they need and the high level of purity water-wise, however am struggling with the lighting issue given that I'm using a newer light system.
Many thanks once again for taking the time to read my ramblings,
<Mmm, do you have a specific question? If not, please peruse here:
the last two trays... I would become familiar w/ the term PAR values, and seek to provide a minimum value of "100" PAR at whatever depths you intend to situate all this life... and go with one of the two easier Tridacnid species... Bob Fenner>
Dear Bob,
Many thanks for replying, my curiosity is to whether corals with high intensity light requirements such as the bushy Acroporas (specifically Acropora kirstyae) would not just survive but thrive under LED lighting?
<They can indeed... I have observed them in several hobbyist and commercial settings doing so>
I'm aware that my current lighting wouldn't be sufficient for such creatures, however am torn between increasing the number of LEDs over the tank (cheaper in the long run in terms of electricity usage, but not certain if the corals would be at their most colourful/good rates of growth) or opting for a (more traditional) set up using metal halide
lighting (expensive to run, but if correct lamps used for Kelvin/PAR ratings then excellent and proven results). Given that my tank is 101 cm long, 41cm wide and 61cm deep I'm currently favouring a rig using two 150W halides plus two T5 actinic lamps plus blue LEDs to give a moonlight effect to the tank.
<Mmm, the "moonlight" is for your appreciation... Sufficient wavelengths/band-width of such "blue" spectra are provided (though masked in appearance) by your "white" lighting for functions' sakes>
You really must be sick of all the lighting questions you receive (!),
<Heeee! Not yet... the field is, uh... (groan!) very illuminating... and much in flux (Sorry, can't help m'self this AM)>
all I can say is that the WWM site has been absolutely invaluable to me and I'm continuing to learn more and more everyday, and in so doing finding out that I actually know very little indeed!
Many thanks,
<It's an investment... and only time and your perception, judge can and will tell in time whether this or t'other (MH) was "the" route to go. I do think/believe that w/in a few years, LED lighting will greatly improve in ap.s in our interest and the cost per unit decline abruptly and greatly.
Cheers, BobF>

Subject: SPS question, colour correlation w/ light intensity
Love your web site!
Many people say that orange or red polyp SPS are doing better in medium lighting...is this true?
<In general, yes... Most "warm coloured" sessile invertebrate life, algae... that has predominant pigments in these colours is adapted for lower light (intensity) conditions... occurs in deeper, more out of the light settings. Bob Fenner>

SPS Tank Lighting/Reef Lighting 3/14/10
<Hello Orestes>
I Hope all is well.
I have read your site countless times but am someone who likes to "hear it straight from the horses mouth".
<Well, you got the right guy, I'm the oldest horse in the stable.>
I have a situation that I was wondering if you could help me with. I just recently converged two tanks 65 gal. and 30gal.into one 110 gal; and want to begin collecting SPS corals for my tank. The tank is 60"x20"x20"acrylic and I have currently running one 175 watt 1000k HQI along with two 65 watt 460 nm actinics about 8" from the H2O level. The entire substrate is well lit. Do you think that there is enough light in this system to keep SPS healthy along with feeding?
<Should be as long as you keep the corals four or five inches above the substrate and position them in the area of the MH lamp. If you do not intend getting another MH fixture (which you should), I would replace the two 65 watt actinics with 14K lamps.>
I just started using C-Balance in my tank. I want to get the Calcium and Alkalinity to where they need to be, before I purchase my first SPS.
<And do not forget magnesium, very important as it enables the corals to better absorb the calcium present in the system.>
That's another question. What is a good beginner SPS? I would much rather get the answers I need from you guys since most of the LFS just want to make a sale, and will tell you anything you want to here <hear>. Looking forward to your response.
<Most SPS corals are going to require more intense lighting than what your system is providing, so in lieu of that, I would suggest you start with LPS corals or even soft corals. A few that do well under moderate lighting and are fairly easy to maintain are short tentacle Plate Corals, Candy Cane, and Trumpet Coral. Do read here and related articles/FAQ's.
James (Salty Dog)>
Thank you.
Re SPS Tank Lighting/Reef Lighting 3/14/10 3/15/10

Thank you for the quick response,
I really appreciate the insight. As far as my lighting is concerned.
Instead of replacing the Actinics (Super Blue), can I change my 10K HQI to a 14K HQI I have to buy a new one anyways.
<You will just worsen the situation as far as needed intensity with your particular system. SPS/LPS corals are found in shallower waters and do better with 10-14K lighting, so with your lighting set-up, I would go with 10-14K on all lamps to get as much intensity in this Kelvin temperature as possible. The 10-14K lamps have enough light in the 440-460nm range to aid with photosynthesis, it's just difficult to see with the naked eye. If you like the appearance of actinics, and would like to use them, and maintain SPS/LPS corals, then I would suggest getting another HQI fixture and run both with 10K lamps assuming this is a DIY set-up.>
<You're welcome. James (Salty Dog)>

Yet another SPS lighting question 2/21/10
Is there a comprehensive list of PAR requirements (compensation, saturation and photoinhibition points) for SPS?
<Mmm, a few sources of such information, yes>
If not, are these general conclusions accurate: The optimal PAR (i.e., saturation) for the average Acropora sp. is ~300, Acropora millepora sp. is ~200, and that PAR above ~650 is usually too high, with the exception of a
rare few SPS?
<I'd go along with these values, yes>
I found a partial list compiled by Dana Riddle at
arist.com/2007/3/aafeature1#h10>, Table 1. Do you know of others?
<Just in the scientific literature. See here:
Bob Fenner>

SPS Lighting (And Tang Selection) -- 02/07/10
Hello Crew,
<<Hi Daniel>>
I'm in the process of building a 100 gallon SPS reef with a water level of 20 inches and 52 inches long. My plan is to illuminate the tank with two 250 watt halides.
<<This is fine'¦though you could do quite well with slightly less powerful; and less power hungry, 175w metal halides here as well>>
The lamps will be 5200k (BLV TOPFLOOD HIT 250 dw E40).
<<Mmm'¦ I'm sure the much lower price of this particular bulb makes it 'attractive' to your wallet, but I think you are going to find it's not so 'attractive' to the human eye>>
Will this lamp replicate the proper environment for shallow water Acropora?
<<As far as meeting the needs of the coral, yes>>
I do plan to supplement them with royal blue LEDs to make them more visually pleasing.
<<Even so, I think you will find this 'less than pleasing' to your eye. Although more than twice the price, speaking from experience I think you will be happier with the 10000K version (BLV TOPFLOOD HIT 250W Cool White E40)>>
My second question is regarding the clown tang (Acanthurus lineatus), does this fish become aggressive only towards other tangs or does its aggression spread to smaller fish like the Anthias?
<<Aggression is mostly toward other tang species or any species that may challenge its dominance of the tank. While it is not likely to be aggressive toward the smaller fishes, such a boisterous fish does not make a good tankmate for the Anthiines (please read here and among the associated links: http://www.wetwebmedia.com/anthiina.htm)...not to mention this tank is really too small for this large and difficult Acanthurus species (please search our website re 'Acanthurus lineatus''¦you can start here: http://www.wetwebmedia.com/AcanthurusBad.htm). If you must'¦ Acanthurus japonicus or Acanthurus pyroferus would be much better choices>>
I would like to thank you for all the great information that you have made available.
<<A collective effort'¦you are quite welcome>>
Daniel Naveen
<<Cheers'¦ Eric Russell>>

DIY LED bulb selection for SPS 2/1/2010
I'm building a 18" cube reef system and want to grow SPS with a DIY LED lighting system. I know that the beam angle and luminous intensity (mcd) determine the lumenous flux (I.e., lumens). There are plenty of LED calculators out there to help me with that calculation. I see on several websites that photosynthesis occurs primarily in the 400-550nm and 620-700nm ranges, so I'm guessing LEDs somewhere in those ranges would be necessary. Can you give me your recommendations on the specific LED wavelengths and recommended minimum and maximum lumen range for each wavelength for best SPS growth?
<Unfortunately I cannot, however, a Google search using the string" <LEDs coral photosynthesis> yields a good deal of useful information. Please do report back on your findings, results. Bob Fenner>

Lighting for SPS and Clams -- 01/27/10
I just got a custom 75 gallon aquarium; the dimensions are 24"W X 30D" X 24" H.
<<Interesting dimensions'¦the long depth should make for a very interesting 'view'>>
I plan on having a 6" deep sand bed, so the height will now be around 18". I would like to know what type of lighting will be best if I plan on keeping SPS and clams.
<<My fave is metal halide'¦though you could make T-5 HO work here as well>>
I will not run a chiller, so I'm wondering if a 150 watt MH will be enough?
<<Possibly'¦with a good reflector>>
My other option is 2 X 65 watt PC, with a 70 watt MH.
<<Mmm'¦this combo will likely give you better 'spread,' but may prove marginal for very high light-demanding species (e.g. -- Tridacna crocea). Much will depend on placement of the livestock. A higher wattage unit will give you more flexibility re>>
I have a 250 watt MH but I feel it might be too much.
<<Not at all'¦in my opinion>>
Can you please help me figure out which will be best?
<<For what you want to stock in this tank, I would use the 250w MH. Suspended above the tank in a 'large' quality reflector like the Lumen Max Elite from Sunlight Supply, or even the Lumen Bright from CoralVue, would make for a very striking display. The 250w lamp also gives you some flexibility re adjusting the height of the reflector up or down to control temperature or light intensity as/if needed>>
<<Happy to share'¦ EricR>>

SHO Fluorescent question for Dana Riddle 1/26/10
Aloha Dana,
<Will forward to him>
Hope you're enjoying the Kona life.
<Am sure he is... there off Ali'i Dr.>
I'm building a 16' or 18' cube Nano SPS tank. I want as much of the setup to be DIY as possible (because I like DIY and because I like to prove that you can have a nice reef aquarium without having to spend a ton of money). Due primarily to the low purchase and operating cost, and the potential suitability for SPS, I want to give some of the newer 6500K CFLs a try. Even if I have to replace them twice or three times as often as MH, they're cheaper to buy and operate, and won't parboil the fish like a MH would with a Nano. I've found two types, the Super High Output (SHO) CFLs with integrated ballasts that will fit into a standard socket, and the LoA Fluorex bulbs that require an external ballast. I can't find a whole lot of details on them, except that they state that their 100W bulbs put out 10,500 lumens, the equivalent of a 1,000W halogen. They also claim an 84 CRI. I can't find a spectral distribution chart to compare them to the MH bulbs.
<Close enough>
A few questions. Are they tri-phosphor?
<Lo dudo>
Have you performed a spectral analysis on any of these bulbs?
Do you think they'd be suitable for SPS (with or without actinic supplementation) with my Nano? Has anyone done a side-by-side analysis comparing the aesthetic and SPS growth characteristics of these high-output fluorescents and MH bulbs with similar characteristics? If you think it's feasible, I want to give it a try.
<Really? BobF... aka Dogfish if you recall>
Re: SHO Fluorescent question for Dana Riddle 1/27/10
Aloha Dan & Bob,
<Howdy Dana>
I have some spectral data on a few CFL lamps, including some of the specialty spiral lamps sold at Home Depot. I don't have that info with me (I'm in Jacksonville for a conference, Atlanta next week, and Honolulu shortly thereafter).
Please remind me in mid-February and I'll get that to you. For now, those fluorescent lamps should be suitable (though I would personally mix in one of the blue lamps sold at Home Depot). I'm using a 13w spiral daylight CFL on a refugium and it promotes calcareous algal growth as well as Chaetomorpha.
<And you, a hu'i hou, BobF>

Lighting Recommendation (T5 or MH) -- 01/21/10
WWM Crew,
<<Howdy Daniel>>
I am planning an upgrade (within 6 weeks) of my 58 gallon reef/SPS system (36X18X21) to a 150 gallon deep dimension reef/SPS system (36X36X27) and had a question about lighting.
Will T5s be sufficient for SPS corals in a tank with a height of 27inches or are metal halides in my future?
<<Well I have to tell you Daniel, I'm a big fan of MH lighting as I think it provides the best look as well as the most bang-for-the-buck'¦especially on deep tanks. But I have also seen some quite nice systems under T5 lighting'¦including some tanks in the 24' deep range. As long as you maximize the number and wattage of the bulbs over your tank, and place the most light-demanding organisms in the upper-half of the water column, you should be fine to continue with T5 lighting on your 150g display>>
I currently have 6 - 39W T5s over my 58 gallon which has a height of 21 inches and have no problems providing the needed light intensity/requirements for my current corals (Pocillopora damicornis - 6 inches from the water surface, Montipora capricornis - 12 inches from water surface and Seriatopora hystrix - 12 inches from water surface).
<<Indeed'¦but as you demonstrate, placement of the organisms is key>>
I will need to add more light to what I already have for the 150 gallon system but don't know if additional T5s will do the job.
<<They should, yes'¦especially with an eye toward more 'daylight' bulbs vs. 'actinic'>>
I don't want to stack live rock 24 inches high to enable placement of corals for sufficient light.
<<This should not be necessary>>
Also, if metal halides will be required, what wattage fixture would you suggest? (I was thinking about one - 250 watt fixture that would move diagonally across the tank supplemented with 4 - 39W actinic).
<<A single MH pendant on a rail system to track across the tank would be very interesting. A 250w unit would likely suffice, but for such a system I would be inclined to go with a 400w bulb/fixture to maximize light intensity toward the 'fringe' of the lighting footprint'¦and use one of the better 'large' reflectors like the Lumen Max Elite from Sunlight Supply or the Lumen Bright from CoralVue>>
Thanks for sharing your knowledge and maintaining such a great site!
<<The pleasure is ours>>

Color Spectrum in Reef Lighting 1/20/10
I need some help on SPS lighting.
<<Hello Terrence, first off I'd like to apologize for the lateness of our reply, typically we answer all emails within 24 hours if not sooner but every now and then they slip through the cracks. I hope this response finds your animals healthy and well and that it is still of some use to you.>>
I have a standard 75g tank with 250w 10k bulbs.
<<How many? I'll assume (which is dangerous, that you are running two.>>
I intend to keep Acro. and Monti. in the tank and have recently added my first Acro. corals to the tank. I ordered them from Live Aquaria's Divers Den. In my tank they look brown. I noticed that they keep there frags in 20k lighting.
<<Of course they do, they look better and sale better under the bluer lights.>>
Should I change my bulbs to 20k to get the color I see the coral when I buy it. I notice a trend for Wet Web Media to suggest 10k lights however every tank I see that has good coloring in there SPS corals are kept at 20k. Would I reach the point of diminishing returns with the 250w 20k at 20" deep or would I have enough light at the bottom to keep Monti. corals and lower light Acro. ? I know its a balance of usable light vs. aesthetics but I cannot fathom keeping a tank full of brown just to get good growth.
<<We do tend to recommend 6,500k to 10,000k lights for zooxanthellae hosting creatures, because they are the most common and closest available lights which match the spectrum of sunlight that you would find on a coral reef. 6,500k is actually closer, and 10,000k is somewhat of a compromise because of aesthetics. Now as you have noticed some folks prefer the bluer spectrum, in which case I would recommend supplementing your halides with a fluorescent lighting system around 20,000k. If the only option for you is to switch your Halide bulbs, I wouldn't go all the way for 20k, I would compromise at 14k.>>
Thanks in advance for your input.
<<Good luck, and I hope this helps -- Here are a few articles I would also suggest;
Check out the latter for in depth technical details, by Dr. Sanjay Joshi he is the 'lighting' authority in my book.
Adam J.>>

SPS Lighting Downgrade (Color Change?) -- 10/23/09
Hello crew,
<<Hey Matthew>>
I am noticing my sps are fading colors under my new 400 watt 20 k lighting, also upgraded reflectors to Lumenarc's.
<<Mmm, good reflectors'¦but maybe 'too much' for the tank here, when coupled with the 400w MH>>
I am going to go back to 250's because the 400s are running too much electricity and chiller operation is non-stop.
<<Not uncommon'¦though you could simply try raising the lights a few inches which could help on all counts (reduced intensity and reduced heat = reduced chiller use = reduced electricity)>>
I have pictures of my sps when they were under 250s and their colors are much more vibrant.
<<It may simply be a matter of acclimation/time to resolve'¦but it is likely your corals are receiving much more photosynthetic energy than they need/are used too and are producing an over-abundance of Zooxanthellae which is clouding the more colorful protein pigments you have become accustomed to seeing>>
Main question: Will my sps return their colorful pigments after a few months or so under less intense lighting?
<<Corals change color/make adjustments to varying water quality and environmental conditions all the time. If an increase in light intensity is the cause for the change you have witnessed, then yes, reducing the light intensity should also affect a change. And while in my experience in such situations it is likely the corals will revert to their previous colors'¦there is also some chance they will not/will revert to something a little different. Akin to the subtle differences you sometimes see in frags from the same colony kept in different systems>>
<<Happy to share'¦ EricR>>

Small Marine Aquariums
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Small Marine Aquariums
ook 2: Fishes
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by Robert (Bob) Fenner
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