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The Real Kona Gold... Yellow Tangs off of HI. 

use of natural lighting (Solatubes) 10/4/10
Am looking into setting up a large system with as main lighting 7 14" Solatubes supported with about 24 T5 (14000K) and strips of Blue LED's which will be used several hours during the day and in lower capacity as moonlights.
Anyway it seems that a lot of reefers are against the idea of using natural lighting though I do not understand why?
<Neither do I.>
I live in Thailand so the days of sunshine and intensity of the sunlight year round would not be an issue here.
Though still a lot say it would not be enough (even local reefers) and the system need to be supported by MH?
<I don't think so at all.>
I have been trying to find some research materials online about using natural lighting in reef tanks but not a lot is written about it?
<Very little out there on the subject.>
I see some reefers using natural lighting successfully but they are very rare and hard to find.
<It is rare. Many reefers tend to be conformists. The fact is such lighting can be very successful.>
Now what would be the verdict of the lighting specialist of WWM on using natural lighting (again supported with T5 and LED so not exclusively sunlight) again considering me living in Thailand and the Cons and Pros about it and please explain.
<I think you could be very successful doing this. I know of one fellow in Texas that has done exactly this with great results. Your big con here will be the initial cost of the tubes. It is not terribly common, but
natural sunlight to support the home aquarium is a very viable option. With 7 14" tubes you will be able to bring in quite a bit of light to the tank.>
Or could it be the unknown is the devil syndrome?
<Welcome, Scott V.>

PAR values on ocean reefs?  12/11/09
Hello Crew,
Im trying to research a few things and one of which is par values at ocean reef locations.
<And at various depths...>
I've found generic readings but nothing specific to location, whats growing there and growth rates of possible.
<Oh, and let's speculate what other factors are involved... water clarity, wave action, currents, the types, concentrations of food organisms and predators, competitors... There is a huge body of data on just PAR and Lux
measures around the world's seas... Some compilations (e.g. books) but mostly scientific papers. Likely a search/trip to a large/college library with aquatic biology, oceanology as majors/electives is called for. Please read here re:
I appreciate any help.
Thanks ahead of time.
<I ask of you to please compile your experiences, reflections here... into an article (for sale in print 'zines as well as electronic). I pledge to help you "sell this work" into the media, popularize your expanded, cross-science findings. I think you will be surprised to find that captive systems are substantially different (more "regular", overlit...) than
natural. Enjoy the process and do report back. Bob Fenner>

Re: PAR values on ocean reefs? 12/11/09
<I ask of you to please compile your experiences, reflections here... into an article (for sale in print 'zines as well as electronic). I pledge to help you "sell this work" into the media, popularize your expanded, cross-science findings. I think you will be surprised to find that captive systems are substantially different (more "regular", overlit...) than  natural. Enjoy the process and do report back. Bob Fenner>
That's what Im working on is the difference between "steroid"
lighting and what reefs actually get, all the variables plus others are all factors but the intent of the article is risk vs reward. Are we in a way forcing the corals to adapt where in a future use they couldn't be reintroduced to the wild because of becoming in need of such intensities. I will shoot ya any progress I make and by the way this is Justin from Modern ReefKeeping, just thought Id start somewhere and WWM seems to be the best place for info.
<Ahh! Do make it known if you're about in San Diego... I'll gladly take you down and around the S.I.O. library for a brief introduction on searches/searching. Thank you for your efforts Justin. Be seeing you, BobF>

Quick Question on Ambient Lighting  9/20/07 Hi All, <Hi Michael, Mich with you today.> You've been a tremendous help to me in the past. Thank you for all the advice. It's probably saved countless numbers of my aquarium inhabitants. <Wonderful to hear!> Here's my question. I have a 60 gallon tank that is located above my office desk. I really enjoy being able to look up from my work occasionally to see what's happening. <Very nice!> The tank lighting is on a timer, but I often work late and need the office lights on. Of course, this results in the tank also being illuminated to some degree. Is this a problem for my fish, inverts, or corals? Does it disrupt their natural cycles? <It is possible for this to have some kind of effect, but it is unlikely it would cause any substantial harm.> If so, should I cover the tank after the lights go off to keep out the ambient light? <I would not worry about this. An aquarium is not exactly the most natural environment to begin with.> Looking forward to your response, Michael <Just keep enjoying your tank! Mich>

Natural lighting, liner sump, SW   3/8/07 Hello,     I am making a 5' x18" x15" high plywood tank with a firestone rubber liner. Will I have any problems using this liner? <Mmm, no... is very stable, biochemically inert> I am going to place sand beneath the liner, building it a bit higher in the corners, to soften and keep the liner from having to make a 90 degree angle. I am placing the tank beneath a south facing window for lighting. I am in Maryland. Should I add some actinic lighting or just leave the natural. <Actinic is principally "for looks"... Suit yourself> I am lighting an anemone on one half of the tank and some softies on the other the tank will be divided). I am using the 75 gallon that all inhabitants are in now for a sump/refugium. I have heard about algae problems when using natural sunlight. Is this a real issue if I keep water quality as it should be? <Mmm, not really an issue... Natural light is used by many, if not most all newer public aquariums...> There will be 3 inches of live sand and 105 pounds of live rock in the main tank. The new plywood tank will be a display tank from the top only, I have always liked this set up and am excited to get it up and running! Any suggestions would be very appreciated!! Thanks for all your knowledge and help!! <If you can, I'd make this liner tank much, MUCH larger... for all the benefits. Bob Fenner>

Re: natural lighting   3/8/07     Wow! Thanks, I'm a big fan of yours Bob!! If you ever want to trade lifestyles let me know! Imp a carpenter, never get to dive and am limited with space and budget to only this one tank! <Wish I had more time, knowledge and skills to do woodwork...> Its fantastic! haha Kidding, actually am happy to have what I have.     Anyway, I got the liner tank set up late last night. There are no other lights except natural. I am very pleased so far! I like the vantage point of looking down on the tank. This was my first attempt at moving an attached anemone. It was nerve wracking! I managed it without damage! <Imagine doing this in the wild... sometimes with HUGE specimens (bigger than trash can lids)... stuck, and I mean STUCK to irregular surfaces... Much patience...> He is attached already, right where I wanted him!! How often does that happen!! The toadstool and finger are happy, open polyps. All others are doing well. I am going to keep the shade down with the louvers open for a few days so they can adjust. They were under two 10k 175 watt metal halide before. One of my gold banded shrimp molted last night after the move. I thought they only did this when conditions were good. <Mmm, or bad, stressed... mostly> I suppose now that it can be stress induced as well. <Oh! Yes> I want to add clowns, probably tomato, or clarkii, and a small school of Chromis and that's it. I am thinking that if the clowns (pair) take to my LTA, they will keep the Chromis away from it. If not, ohh well, it wouldn't be a bad meal for it, and they are only 5 or 6 dollars. Anyway, thanks for the response!     Rob <Welcome. BobF> SW sunlight use... solamente?  11/21/06 My current tank holds SPS, LPS and softies, receives +-4 hours of sunlight everyday, winter or summer. I don't have a problem with temperature its constant on 27 C. I don't even have a problem with algae. I visited a few public aquariums and they are using sunlight for there corals. <Ah, yes... natural light/ing has been used for this purpose for many decades> I am thinking of building a new tank but using only sunlight as lighting via skylight or solar skylights. <Can be done> Is sunlight okay to be used as the only source of lighting? <If there is sufficient, consistent availability, yes> Will I still get the same colour from sunlight than from MH or T5's? <Can. Bob Fenner> Thanks    Mohamed

Supplemental HQI Lighting On A 900 Gallon Tank   8/6/06 Salutations! <Hello Tim> I'm currently in the process of setting up a rather large aquarium, a 10' x 4' x 3' monster (3 feet deep). The tank is acrylic, and has 3 large 30" square cutouts on the top. My setup is as follows: 1) I live in Arizona in a house with a flat roof. 2) I installed 3 24" Solar tubes in the ceiling directly over the tank.  The tubes extend down to about 18-24" off the top of the tank, and don't precisely line up with the cutouts.  The two on the ends are slightly to the outer edge of the tank, and all three are more towards the back of the tank. (Joist placement issues) 3) The tank is in a dedicated room, (front of the tank is picture-frame style into the living room) so aesthetics of the fixtures is unimportant. 4) I plan to dedicate this tank primarily to shallow water SPS and clams. I suspect that the three solar tubes, while providing a huge amount of light and hopefully offsetting my electric bill, will not be enough light for this tank.  I also think that for aesthetic reasons, I will need some blue or actinic lights to offset the natural sunlight coloring. Along those lines, my current thinking is to add three 20,000K 400W HQI MH fixtures to the tank.  However, because of where the tubes are, these would be centered more towards the front 1.5 feet of the tank.  I'm concerned that alot of my light will go directly onto the sandbed and the living room out the front face.  I was thinking perhaps I could angle the fixtures towards the rear of the tank, but I'm not sure if this will cause a high loss of light through reflection off the water surface.   The other option would be to put 2 halides over the braces between the solar tubes, but I am concerned about the effect of the high intensity light being directed directly at an acrylic panel. I suspect I will end up mounting a fan on the wall blowing crosswise across the entire tank to keep the heat down.  Also, the room is air-conditioned. So: What kind of supplemental lighting would you recommend for this setup? How would you position the lamps? Is a 400W HQI too much power? Maybe some other combination?  I can always also run them for only a few hours each day to simulate a mid-day-sun. Any other thoughts on lighting this monster? <Tim, a few questions before I can proceed.  First, is the tank currently set up and running?  If so, are any SPS corals or clams in the system at present, and, how are they looking with just the solar tubes?  James (Salty Dog)> Tim  

Re: HQI Supplemental Lighting on 900 Gallon Tank...Mmm, How Many Solar Tubes Per Gallon?    8/7/06 > <Tim, a few questions before I can proceed.  First, is the tank currently set up and running?  If so, are any SPS corals or clams in the system at present, and, how are they looking with just the solar tubes?  James (Salty Dog)> No.  The system isn't up and running yet.  I'm just about to add live rock and begin the cycling process. As far as the lights.. I think my primary concern is not to over-power the corals.  I realize I may be in a bit of uncharted territory here.  I will say, that the tubes light up the whole living room through the tank, and the light rays seem to be fairly direct, as I get the ripple effect like a MH light would. But hey.  I'll have the most accurate moonlight system of anyone. <Tim, to be honest with you, I'd see how things go with just the tubes.  You may have enough light light here along with eliminating heat problems from 400 watt lamps.  See if your investment works before spending more money.  Also, in future replies, please include/reply to previous correspondence.  James (Salty Dog)> Tim Solatube Lighting? - 08/04/06 Hey guys, <<...and gals>> How's it going? <<Well, thank you>> I've got a question that I don't see asked anywhere on the Web. <<Okey-dokey>> Can I use a tubular skylight as my primary source of light for my reef tank? <<Mmm...have seen this asked/discussed before>> I would have just Moonlight LED's for the night, but is that enough for plant growth, or do the lenses block/distort too much light? <<I don't think the lens (dome) is a problem, no more than the light shining through the window on your terrestrial plants...but other issues to consider here>> I've seen people say they are equivalent to 700W in December, and 1200 watt in June.  I just am not too sure about the frequency and intensity.  If I did it, the tube would end up right in the canopy.  This is only an idea and I probably won't be doing it for a while, but I can't find anyone else that talks about light quality. <<Seems sound, even "desirable" in theory, though I've never seen/heard of it actually being employed.  For it to work you would need to be located in a region where you receive sunlight of sufficient duration/intensity...then there's the issue of radiant heating...  But not to discourage...  If you're willing, I think it might be worth experimentation.  I'm sure many here would be interested to hear your findings re>> Thanks! Keep up the good work! Eric <<Regards, EricR>> Re: Solatube Lighting  - 08/05/06 I saw this email posted on the daily FAQ's and thought the inquirer might want to read this thread on Seahorse.org.  It sounds like a couple of people are about to give this a shot. http://forum.seahorse.org/index.php?showtopic=27365&hl= It can be found in the "Helpful hints and do it yourself" forum, titled "Tubular skylights".  I just thought I would share the info, Jessica Groomer <<Thank you for sharing Jessica...will post.  Eric Russell>>

SW to light or not    4/10/06 I have been interested in setting up a 30 gallon saltwater tank with live rock, fish possibly some invertebrates <Very cool - have fun with it!>, the unusual thing is i would like to run the tank with just natural sunlight. <Ok...> The tank would not have any light loving inverts, but a pygmy angel some shrimps, <Ok...> live rock and a sand bed about two inches. The tank will be placed near a window that gets about four hours of natural sunlight is there anything I should be concerned about. <Actually yes, the lighting in an artificially lit tank isn't as conducive to nuisance algae or algae blooms as a tank lit with natural sunlight.  I would not suggest you do this.  It would take an enormous amount of work to keep the tank clear.  Hopes this helps you make your decision.  Jen S.> Thanks Ron.

Re: to light or not  - 04/10/2006 let's say i do not put the tank near the sunlight would that work , also what about a refugium that was lit on the tank <I/m not sure what you're asking here.  You're going to want some kind of lighting for the tank.  If its an all fish tank you can pretty much do want you want with artificial lighting.  If you're going to keep inverts too you're going to have to research what spectrum lighting each need to survive.  As for the refugium, you're also going to want to light this - different ways to do it though.  Will you include algae?  Because then you'll need daylight spectrum too.  Your possibilities are endless here. :) This is where you'll have to spend most of your budget for the tank! Do some research on WWM, I know there are many pages on tank lighting.  Good luck, Jen S.>

Sunlight Issues SW  3/14/06 Dear Crew, <Hi Fickie - Tim answering your question today!> This question is posed to Mr. Calfo but I would greatly appreciate help from anyone that has the means to do so. Anthony, I was greatly inspired by some advice you gave a fellow reefer and have since set-about creating a new set-up which will use natural sunlight. Unfortunately due to restricted access of materials and the design of my existing roof and sunroom, I had to go with polycarbonate roofing with built in UV protection. I only just found some posts that sps tend to go brown and suffer stunted growth when UV shielding is present (heat will be sorted through a chiller). I do still have the halides from my old set up, but was hoping to use T5's just for viewing purposes but part of the whole point of this set-up was to avoid using supplemental light as much as possible. My question is will I be able to compensate adequately for UV using T5 'violet' lighting? Or should I just pack in the whole project? I do remember you saying in BOCP that any sunlight would be beneficial, I just need some direction before I pump yet more money into this project. <I would very much recommend that you continue to use your metal halides, relying on natural sunlight only as a supplement. Unsure as to your location, I can only say that most locations will not offer sufficient sunlight to maintain SPS corals - especially during the winter seasons it will be necessary for you to use artificial lighting to ensure the continued health of your corals. Therefore my suggestion is as follows: by all means, do use sunlight to help brighten your aquarium, and as a means of providing a more natural light spectrum, but also continue to use your metal halides as sunlight alone will in most cases be inadequate as the sole source of lighting.> Finally, to the entire WWM team, thanks a stack for this site and the help you offer. I would certainly be more 'stupid' without it. <Always a pleasure!> Regards, Fickie

Sun Mirror  1/21/06 Thanks again for your help.  I'm hesitant to ask this next question, but here goes...am I creating problems by using a large mirror to direct sunlight from a window into my tank? <No.  James (Salty Dog)>

Natural Sunlight/Coral Growth/Closed System 2/10/04 Hello Wet Web Media <cheers> I did find some indirect articles on the site regarding natural sunlight but had a couple of questions  With the cost of lighting I am always looking for alternatives --- I have a 75 gallon reef with hammer corals, bubbles, a cabbage leather, a xenia, a plate coral and a long tentacled anemone.  The tank is .75 percent filled with live rock and heavy skimming.  I run carbon a couple of weeks a month.  My parameters are in range Calcium, pH, dKH --- The temp is a consistent 78 degrees. The lighting includes 3 VHO lamps  95x3 = 285 and one Actinic 1x40 = 40+285=325 watts.  The tank receives a full day of sunlight from the back of the tank and so far for 10 months no real algae problems except for occasional small outbreak of diatom on the window which the Turbos usually keep in check.   <as it should be... its a lie/wives tale about sunlight causing algae. Excess nutrients with any light cause algae> My question is how much of that sunlight through glass is actually beneficial to the system?   <er... as much as possible mate. These organisms did come from the reef not too long ago ;)> The coral expand every day but I know corals can open and still be in a gradual decline.  Generally speaking (I understand you just know just the few things I told you about my system) Is this lighting adequate for the animals/corals mentioned?   <seems so> Is there any good success stories with coral growth and natural sunlight in a closed system??   <ahhh... there are perhaps tens of thousands of pages of success stories on the subject across the Internet! I made a living on corals under natural sunlight and wrote a book about it, my friend: "Book of Coral Propagation by Anthony Calfo". Greenhouse grown corals for a decade> Can natural sunlight substitute for some of the needs for additional wattage?? <it can replace all... book orders here ;) https://secure.wetwebfotos.com/order_form.jsp http://www.readingtrees.com/ best regards, Anthony>

Natural sunlight really works! - 2/14/03 Hello crew & I hope Mr. Calfo- <cheers, my friend> I wrote some weeks ago about moving my tank near a window so that it will get about two hours of natural light. I did that three weeks ago and I just want to say it made all of the difference in the world. <excellent to hear> My softies are taking off. I am amazed at the difference. <it really is remarkable and algae growth will be no better or worse than without it> I don't know how it might have affected it but my pod population has exploded. Could the sunlight help them, if so how? <yep... some pods eat phytoplankton which is now growing better from the sunlight> One more question. My skimmer has slowed down some. I still get a lot of skimmate but I would say a 1/2cup less then before. <per day... per week?> Is that due to the new lighting? <not likely. And not a problem if that is per week. Else, there is a tuning problem> My specs are Alk 10dkh, Ca400, ph 8.3 No2 0 No3 0 Amm 0 Thanks Mr. Calfo, I enjoy your book and am looking forward to the new ones coming. <Thanks kindly!> Have a good Valentine's day. I had to send this letter out before I rush and get some flowers for my g-friend. Karl <cheers, Anthony>

Lighting for Corals Hello, I have a 38 gallon and two 20 longs I hope to raise corals in. Low limited income forces me to stay away from MH lighting or other high output set ups. <actually its your tank size that spares you from the commonly used and abused MH lighting rage that too many aquarists are on> In my search I have yet to come across information regarding supplemental sunlight through an (East) window. <there is quite a bit of information on this topic on message boards, articles and in some books (my Book of Coral Propagation for a shameless plug). South facing windows are preferable, East is a good runner up.> I know glass does filter out some wavelengths but my house plants do fine. <agreed on premise, but a horrible analogy or line of thinking. Terrestrial plants have tremendously different needs (light spectrum and intensity) from light through air than corals in water> Why wouldn't this work ( with added fluorescents) for coral? David <it would work very well with supplemental fluorescents my friend. The LPS corals you have mentioned in your subject line would literally bleach and die in time (months) from photoinhibition under halides in a tank this small. Besides, these corals like most are actually very easy to feed (finely minced meaty foods almost daily)... and feeding can compensate for deficiencies in light (but the opposite is not true). Best of luck! Anthony>

Fresnel lighting? Hi guys, I was just snooping around WWM looking for new mischief and saw a link to a site that provided solar illumination in housing (the link has since died x_x) and it reminded me of another link I once mulled over quite a bit... http://www-personal.umich.edu/~bclee/lens.html Looks like a Fresnel lens is pretty amazing at capturing and concentrating light rays.. I've always wondered if one could be used outdoors to funnel light into the house (say, through a series of mirrors or fiber optics) and then down into an aquarium. Obviously the light output would vary depending on the weather, but one could argue that that's more natural anyways, or perhaps it could be controlled. Any thoughts? I'm a big clueless in the light energy department but thought this was fascinating. And if by chance my car tires have been melted when I get off work.... I never trusted Calfo's grin.... Regards, Stefan <Such natural lighting conductors can work to advantage... as you hint, with control, augmentation due to the vicissitudes of nature... worth investigating, experimentation. Bob Fenner, who does trust Antoine's antics, expressions> Halides soon to be inferior? Just saw an interesting article about channeling sunlight into homes, who knows maybe we can light our tanks with this technology someday! Sunlight in the Home <Thanks for sharing. That certainly is interesting. Mike G> 

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