Alright Newbie; Let's shed some light on this subject.

[BigBert96]

Well im new here too, and I kind of like his rhetoric!!! Its all in good humor anyways so whats the fuss about?

[lillibirdy]

I am thinking Fishboysv is pulling our leg... (a belated April fools joke maybe)....because certainly even most newbies will recognize tounge in cheek when they read it.... If not... I hope he doesn't read the "turn of your skimmers" thread..., or ask his LFS for an elephant nose yellow Tang......lol.

This is a very entertaining AND INFORMATIVE thread (& egroup)! Best answers to my lighting questions I have found, (and I been looking)! Thanks Waterkeeper for dummying it down for us thick headed types!!!

Anxiously awaiting the next installment...

KathyW

[Dr4g0nf1y]

I still want to know if all this lighting will let us keep polar bears. :-)

[WaterKeeper]

I know what the problem is with Fishboy. He never got one of these--

Hi Steve

To Reef Central

I've reported WaterKeeper countless times to the Mod's but they never do anything about the guy. If I could figure out how to use my ban button he would be history. Anyhow, until then we'll all need to suffer through his obnoxious posts like this one--

Ok; Let's make some Waves! As you were! I heard some of you Navy guys snickering in the back. We're talkin about light waves here.

Oh boy, now I'm going to be in trouble with the Navy too.

To this point I have been discussing light as if it was composed of discrete particles. Looking at light in this fashion makes it easier to describe some of its properties and indeed light does at times act like particles. If one looks at light emitted from a laser it would appear that light is composed as particles. In a laser the emitted photons are projected almost absolutely parallel to the source. They spread very little over large distances thus losing little energy as they move outward from the source. On the other hand, light from an aquarium lamp is more like the blast from a shotgun enlarging its pattern as it travels from the source.

This assumes that light is discrete particles like birdshot. In fact light spreads more like the waves made when a stone is tossed in a quiet pond. It forms ever widening waves that fan out but lose energy as they move from the source. These waves are not two dimensional but actually spheres. In our fragmentation grenade experiment if we replace the grenade with just plain explosive (I always use C-4) our pipes, if soft enough to take the shock, would bulge out in semi-spherical patterns after the blast; the slim pipe expanding more than the large diameter pipe.

When we start reflecting light this way and that, this wave property, sometimes called Huygen's Principle, comes into play. To keep things simple we need to think about two waves forming and colliding at an angle. As the waves combine some crests join together to create a larger wave while other tend to cancel each other out as the troughs and crests intersect. This is known as diffractive interference. It really can create havoc as light bounces around inside a reef tank.

Our Maglite uses a parabolic reflector to channel light in an effective pattern. The neat thing about a parabolic reflector with a point source is, that no matter what angle the light from the point source strikes the reflector, it is returned to the open part of the reflector at right angles. Now if light was a true particle this light would be just like a laser. All the light would be focused in a tight beam. Unfortunately, this is not the case. The light leaves the reflector as waves that spread as the distance from the reflector increases. At the same time the light loses intensity. As we move the Maglite away from the wall the light grows in size but decreases in brightness.

Returning to our shoplight type reflector. It is not a very good system for focusing light as our tubes are round and emitting light around the entire circumference of that tube. It hits this reflector at all sorts of angles and is reflected out at all sorts of angles. When this type of reflector is used in an aquarium hood some of the light is directed down to the bottom of the tank but a large portion bounces out into space. We illuminate the floor and walls of the room as much as the sand bed. Even worse Huygen's Principle comes into play and part of the light waves collide and cancel each other out.

I said in my last post that if we narrow our tube from a T-12 to a T-5 we can use more effective reflectors. By making our reflector into an elongated parabolic reflector we can focus our lights in a more efficient manner. This allows us to get the light to where it will do the most good.

Let's say we have a 120 gallon tank that is 4' by 2' by 2'. We could mount 5 four-foot VHO T-12 bulbs in a shoplight type hood. We would have a total of 550 watts of illumination being produced but because of the light scatter only about 200-250 watts is effectively lighting the tank bottom where we want it. Now if we mount ten 54 watt HO T-5's, each with a parabolic reflector, I know that is a bit of a squeeze, we have a total of 540 watts available to our tank. Unlike the T-12 setup we can channel more of this light to the sand bed using better reflectors. Maybe we can get 300-500 watts to the bed. This is a vast improvement over the poorly reflected T-12 setup. I'm using watts in this case but we are really talking about the lumens that those combinations of bulbs would produce.

Yes Scuba-doo, you guessed the secret advantage of T-5's over T-12. With better reflectors we can get much more bang for our buck with the slimmer T-5's. The T-5's act more like a Maglite beam and provide tighter illumination for our tank while reducing interference between the lightwaves. You can forget the slightly better lumens produced by the T-5 or their ability to work better at higher temperatures. It is the slimmer design allowing better reflectors that is the key.

Someone may be saying, "What about the even thinner power compacts?" The problem here is the design of the tube itself. They are even brighter than the T-5 but that U-tube is a real problem when it comes to reflector design. As is commonly found by irritated reefer's, a PC will break in a magnitude 1 earthquake. The U design helps strengthen and shorten the tubes. That reduces breakage. It also makes it nearly impossible to get the most bang out of their light by designing an efficient reflector.

Next we need to bring MH into this fray.

[mike4271]

Originally posted by lillibirdy
I am thinking Fishboysv is pulling our leg... (a belated April fools joke maybe)....because certainly even most newbies will recognize tounge in cheek when they read it.... If not... I hope he doesn't read the "turn of your skimmers" thread..., or ask his LFS for an elephant nose yellow Tang......lol.

This is a very entertaining AND INFORMATIVE thread (& egroup)! Best answers to my lighting questions I have found, (and I been looking)! Thanks Waterkeeper for dummying it down for us thick headed types!!!

Anxiously awaiting the next installment...

KathyW

Actually, checking his other posts, he may be for real, maybe changed his user name from Richard Cranium.


Keep it up Tom, waiting for the M/H installment

[WaterKeeper]

Well dang Mike. You think he's for real? If the Mods here ever start really reading my posts I don't have much time left before they move me on. I'd better throw in a little about MH (mental health) before they catch on.

[Scuba Oz]

Thanks for the info Tom

fishboysv
you need to read all Tom's threads, its a great style he has, he is not being rude, he is making it a hell of a lot easier for us laymen types to understand all this techy stuff!

[Sierra]

When reading waterkeepers post I sing to myself "HAHAHA HAHAHA HA HA HA HA HAAA" set to the tune of jingle bells.

It reminds me to use my sense of humor, and helps block my urge to scream profanity at my computer.

[WaterKeeper]

Time for some Heavy Metal.

Contrary to what you are thinking I am not ignoring metal halides it is just there is a lot more info posted here at RC and elsewhere on the web about them. Part of that reason is that there are many more manufacturers of metal halide lamps than fluorescent and fluorescent, with the exception of T-5, is viewed as "old hat" by many in this hobby.

Metal halides are often compared to incandescent lights. This is the misbelief that the glowing filament in the MH lamp is the source of the emitted light. In fact the filaments are not connected together as they are in an incandescent. The filaments just maintain an arc, which vaporizes a fill material that supplies the actual light. In this respect they are more like fluorescents. The lamps are started just like a fluorescent. There is a small amount of mercury inside the arc tube. A high voltage is applied to get things rolling. Once an arc is struck between the filaments materials such as sodium iodide, sodium bromide, scandium iodide, dysprosium iodide, and indium iodide become heated and vaporized. When these metal salts are hot enough this now gaseous cloud radiates visible light. One thing you notice with MH lights is that when first turned on they are not all that bright. It takes several minutes for the metal halides inside the tube to vaporize and reach operating temperature. Depending on the bulb they may not reach full output for 10-20 minutes following ignition. Another unique thing about MH is that if you turn them off you can’t turn them back on, at least right away. This is because the hot bulb is full of metallic gasses. If the initial high starting voltage were applied to the still hot tube too much current would flow burning up the lamp but more probably the ballast. MH ballasts have a timer circuit built in to prevent this from happening. Called re-strike time this usually is 15-30 minutes.

MH lights are much closer to a point source than any type of fluorescent. This is both a plus and a liability. As a point source reflector design is simplified. You could use a pendant design with a single ended lamp that was almost identical to that in the Maglite. If you go that route it is important to get a bulb that can be vertically mounted. Unlike fluorescents, MH lamps have a designed orientation. Most are made to be mounted in a horizontal position and vertical mounting will shorten their life.

With MH lighting getting a lot of light to the surface is usually not a problem. They make good spotlights. With an MH we usually need to spread the illumination rather than sharply focus it. If you think about our 120 gallon (4’x2’x2’) tank if we mount two 250 watt MH lamps above it our problem is to spread that light evenly over a 4 square foot area for each light. Fortunately this is fairly easy to do. If you notice on a wattage basis the total watts in this case are a little less than the VHO or T-5HO set-up I used in the earlier post. One of the myths about MH lighting is that they provide far more light than fluorescents. This is true but is not as much as people believe. A T-12 VHO will produce about 70-85 lumens per watt, a T-5HO 85-95 lumens per watt, PC 100-110 lpw and a MH 85-105 lpw. Yes they are brighter than T-12 and T-5 but it is not overwhelmingly so.

As I indicated earlier in this thread we have two types of MH, single ended or mogul base and double ended or HQI. The single ended is shielded and this shield make reflector selection somewhat like the difference between T-12 and T-5 fluorescents. The fatter design of the single ended metal halide makes for a more cumbersome, less efficient reflectors. The slim double ended is a bit more versatile.

The composition of the arc tube is important in MH lamps. There are two types,an emerging technology-Polycrystalline alumina, transparent aluminum Scotty , and high quartz glass. The former will be a wee bit cheaper and will tolerate higher temperatures. It does have a drawback. The metal halide salts are quite corrosive. In the hot gas cloud this can case them to attack the aluminum. The result is that the arc tube turns white and less light is transmitted over time. This happens with quartz tubes too but right now this is holding up the PCA tubes from hitting the market. They should be available pretty soon and promise even brighter MH lighting. Another major drawback is sputtering. We discussed that in fluorescents. That is were some of the filament material is vaporized and coats the glass tube. In a fluorescent this mainly occurs at the ends of the tubes near the filaments. In a MH sputtered material can coat and darken the entire arc tube. Like the etching effect this can reduce light output and also results in a shift in spectral output.

Another drawback to the MH is that quality control is much more of an issue than in fluorescents. Water vapor in the fill gas or the halide salts can cause serious shifts in the spectrum. This is because water decomposes to hydrogen and oxygen in the hot lamp environment. It also makes the atmosphere more corrosive resulting degradation of the filaments. Good lamps select salts low in moisture and provide what is known as gettering. A getter is like a sponge that soaks up unwanted gasses released inside the arc tube thus providing a more stable spectral output.

Well that’s enough for today. We finish this part up and start to pull all this together in the next installment.

[WaterKeeper]

Some of you Rookies must be growing that wacky tobaccy as you can't get enough poop on MH lighting. Well covering the floors, ceiling and walls with Reynolds’s wrap will help the crop but it doesn't take into consideration the interference losses from Huygen's Principle.

I had a little time this afternoon and thought I’d bring this section on MH to a close. Following that I’ll tie up the loose ends and give you my humble idea of proper methods for lighting up you reef.
Not that type reefer dummy!

Another myth about MH concerns that they produce so much more heat than fluorescents. This is a partial myth. The arc area inside the tube is hot indeed, 6000°K or 10340°F for you metrically challenged. Even the area by the arc tube is hotter than Hades running around 1250°K or 1790°F. We are talking real heat here and it is not to be confused with the K scale used to denote apparent color. Touch that double ended while running or even the outer shield on a single ended and you are going to get some serious burns, so be careful. A special little note here to HQI users—even when cool do not put your grimy newbie paws on the arc tube. At the temperature the tube runs it bakes those fingerprints to carbon and fuses them into the tube. Not only does this block some light it creates hot spots, which can cause tube failure.

Now as hot as the tubes get if you place a MH in a calorimeter, a devise for measuring heat production, and measure the heat generated it won’t be all that much higher than the same wattage in fluorescent tubes. In fact VHO or PC, which tends to run hot anyway, can possibly be hotter. The problem is mainly with the type of heat formed. With fluorescent lighting the tube heats and warms the air. Minimal ventilation can carry the warm air away. With a MH lamp the tube does get hot but even worse the lamp emits radiant heat. That heat passes directly through the air into such things as the water and glass tank. That is why even a well-ventilated reef running MH lighting may overheat at times. Usually if your home is air-conditioned, and the tank is less than 150 gallons, this build-up will not be a problem. In large tanks heat is retained longer and a chiller is often needed if MH lights are used.

A good point about MH is how they handle high K values and here I am talking about color temperature. Once fluorescents get past about 8,000 K the luminance drops off. Lights like a 20,000 K are really weak. MH takes a hit but not nearly as much. If you really, really want to sing the blues then MH is almost a must. One other thing about high K lights, blue does have better light penetration in water but too blue a light will omit some of the yellow orange spectrum also useful in photosynthesis.

I’m going to talk about different tanks with different light requirements next. I usually gear my stuff for tanks in the 70-150 gallon range, which is a good size for a novice reefer. I happen to know that some of you newbie’s are not in the mood to fool around and start out with 250-gallon tanks and up. Tanks this size require some serious thought when you plan to light them. For one, they probably will need there own circuits run off the main. It is no fun to have your tank up and running in the family room only to have it trip the breaker when you turn on the T.V. Secondly, the old kilowatt meter is going to be spinning like a top. You want to do some serious research into both the type of lights you use and the brands. Here comparisons like Sanjay's on MH lighting really are a help. With the way energy prices are headed your work will pay off in a pretty short time.

For the rest of you, even those of you with (dare I say it) nano-reef tanks, I’ll get into the options you have in our next illuminating discussion.

[browardreefer]

yay gonna send this thread to all the ppl who are like you neeeeeeeeeeeeeeeeeeeeeeddddddddddddd mh :P

[WaterKeeper]

Broward

Man you read this whole thread this fast? I still won't trust me.

[silkchaos]

Wow, verbous tonite. Keep it coming! All of my lighting questions answered! finally! I see the light at the end of the tunnel!

[JustOneMoreTank]

Ummm, so you still haven't told me which light is the best. I have eels, damsels, urchins, clams, tangs, and lots of LPS and SPS in my 20L.
So should I get the All-Glass PC strip light oak color or three Coralife Aqualight Pro lights?

[Scuba Oz]

Tom, I do have a question. For the current VHO users that do not want to change to this new wave T-5 light, is there an iduvidual parabolic reflector for t-12's also like the T-5's that we can put on the T-12's and make our lights better? If not I am going to the patent office right now!! For real though, is there a reflector we can use?

[AnAnemone]

Originally posted by Scuba Oz
Tom, I do have a question. For the current VHO users that do not want to change to this new wave T-5 light, is there an iduvidual parabolic reflector for t-12's also like the T-5's that we can put on the T-12's and make our lights better? If not I am going to the patent office right now!! For real though, is there a reflector we can use?

.
Yea, is it just a matter of scale?
And thank you for your time in this thread.
TimO

[ebacon]

Notice he is in trouble with the army and the navy.. lives near a air force base but he dosent mess with the Marines!! very interesting thread i must say. it seems that i get all sorts of diffrent opinions regarding my 72" 6 bulb orbit PC setup with moonlights. some say it is fine others warn me not to use clams and certain lps corals.. (or was that SPS??) ahh who knows whats say we just wing it and trust that a 900 dollar lighting system cant be all bad ( fishboy, thats what us humans call a joke.. or humor)

[WaterKeeper]

Originally posted by Scuba Oz
Tom, I do have a question. For the current VHO users that do not want to change to this new wave T-5 light, is there an iduvidual parabolic reflector for t-12's also like the T-5's that we can put on the T-12's and make our lights better? If not I am going to the patent office right now!! For real though, is there a reflector we can use?

The DOE is already working on that now. I recently cracked their top secret web site and found Reflector Development where they are right now working to avoid a "reflector gap" with countries hostile to the U.S.

This site appears to be designed by an ex-marine and sells reflectors Patriot Logistics. There are a ton of sites out there that sell reflectors for commercial and home lighting.

Originally posted by silkchaos
I see the light at the end of the tunnel!

That is where those Maglites come into play.

Originally posted by JustOneMoreTank
Ummm, so you still haven't told me which light is the best.

I like old, neon beer sign lights the best.

[ebacon]

nice

[WaterKeeper]

Originally posted by ebacon
nice

Nice is never a word used to discribe me. Just ask Steve.

[WaterKeeper]

I received a PM asking why all those iodides used in MH lamps have strange sounding names and why are they needed. That’s a pretty fair question so here goes.

The first metals halides were exclusively filled with sodium iodide. They were also called sodium vapor lamps and everyone is familiar with them under the guise of streetlights. Now if you ever stood under a street lamp and looked in a mirror you can get a pretty good idea how you will look with a case of jaundice. Sodium iodide is bright but very yellow in its light output. It was fine for street lamps but there was a clamor for a whiter version of this bright light source for such items as motion picture lamps and billboard lighting.

Under the bridge, where the chemistry trolls hang out, they were busy adding rare earth halides into the sodium vapor. This is called doping and by adding salts like thallium iodide they could add green to the light. Indium iodide when added produces blue and is added in large amounts in those high K metal halides so popular today. Thank to alliens like Sanjay, who is a miner on the planet Mogo that orbits State College, Pa., just about every color is now reproducible in MH lights. I should note that Sanjay is the only being in the known universe that can correctly pronounce the name dysprosium.

By the way Sanjay does have competition in the “measures the output of lamps� contest. Dana Riddle, a prolific writer on reef lighting, has several articles on the intensity of lighting. I was looking for data on fluorescent vs. MH lights and Dana had one of the few comparisons I found. I was not able to find the original document but it is found here. Sorry for the second hand information.

These intensity graphs need a little explanation. There are three, one for VHO, one for PC and one for MH. They show the lighting pattern produced by each type of light as if it is shining down on the bottom of a tank without reflectors. The pattern for the VHO is what one would expect; fairly even illumination along the length of the tube diminishing in intensity as one moves from the front to back of the tank. The PC graph is very similar but the PC produces somewhat greater output. The PC tube is shorter and does not cover a much length as the VHO. The MH graph is much different. Here the point source lighting of the MH is clearly seen. In the center, directly below the light, it is almost four times as bright as the VHO. The light diminishes rapidly as we move away from the MH tube. By about a half foot away from the light it is almost zero on the one axis and on the other only extends out about 8 inches. One should note here that the MH lamp used here is a very blue 50 K MH lamp. If it was a 6-8 K lamp is would be almost twice as bright at the center. This does show one other thing. Even though the lamp is extremely blue it does not penetrate that far away from the source. This indicates that blue light penetration in a tank is not as important as is often made out.

Well we have certainly covered a lot so far. I guess you’ve decided to get a Normal Output, N.O., warmwhite shoplight and hang it over your tank.

Say No to N.O.? Not really. Actually N.O. can be a good lighting choice for the beginner. Many new reefers are on a tight budget. Since their budget is so tight they will use the old 55 gallon that housed their discus before they were forced to eat them after a week of not being being able to buy food.

Now, with better funding, they resurrect the old tank but this time with the intention of going SW. It sounds like a great idea until they find they must shell out $300 or more just to add some rocks into the new tank. Adding it all up there is no way they can afford a few hundred in lights. They are committed to SW but their pockets are empty.

Enter the humble N.O. lamp. They are cheap and ballasts are too. You can mount 3 or 4 over the tank for a song. You don’t even need to have special, expensive aquarium type bulbs. Some 5.5-6.5 K daylight bulbs and maybe one actinic will do the trick. Most new reefers run out and get fish to start. Just like their FW cousins, SW fish don’t need mega-lighting. The coralline alga on the LR is a low light alga and N.O. lights will allow it to grow. Heck, with a little research and creative placement there are plenty of corals that will do fine in a tank only illuminated by N.O. A few watts per gallon are all you need to get started. This allows you time to shop around. You may find a real bargain on RC’s selling and trading forums for some electronic ballasts or maybe on e-Bay. If you replace them with better lights latter on you can use the N.O. for lighting a rock curing tank. They are also fine for a hospital tank or perhap's a culture tank set-up. Don’t let light costs hold you back. It can cost only slightly more than lighting a FW tank.

Next it is on to PC’s.

[ebacon]

okay, so for the sake of argument (as if i dont get enough with BOTH my wives) does a current USA power compact 72" 6 bulb (Dual Daylight10,000K & 6,700Kand Dual Actinic 460nm & 420nm Compact Fluorescent bulb) light fixture hold a candle to the metal halide.. (get it .... candle )

[ebacon]

In other words what corals and other types of marine life can you or can you not keep with one or the other? I know I know, your next question is how deep is the water. lets go with an average and call it 25"

[WaterKeeper]

Originally posted by ebacon
okay, so for the sake of argument (as if i dont get enough with BOTH my wives) does a current USA power compact 72" 6 bulb (Dual Daylight10,000K & 6,700Kand Dual Actinic 460nm & 420nm Compact Fluorescent bulb) light fixture hold a candle to the metal halide.. (get it .... candle )

I'm getting to that e-Bacon.com, also Chris PM'ed me asking if using PC's on his 46 was a rookie mistake. And is that candle power or foot-candles your talking about?

Around 6 years ago to be politically correct one needed PC lighting, at least so I was told. Now WaterKeeper is not so easily swayed by the masses but here was a case where I was. I had an old 29 gallon that was being made into a seahorse tank for a daycare center. The VHO tubes on it where nearing the end of their useful days and the ballast wasn't far behind. As good a time as any thought I for a switch to this super new PC lighting. Since the tank was not going to have anything like clams or SPS I decided to try two 55 watt PC's, one a 6.5K full spectrum the other an actinic. I bought a retro kit with electronic ballast and a total of six lamps, three of each type.

After wiring it all up I switched it on. I was less than awestruck. Yes, it was bright but it also didn't have the right look. Upon closer examination I found that the supposed 6.5K PC was much more yellow looking than the VHO it replaced. The actinic, if you can call it that, was white but surely not what I expect from an actinic and I had been using T-12 actinic since they first started to hit the market.

I had been told the lamps ran hot but not that they got so hot that the cement that holds the lamp to the base deteriorated and the whole mess separated after about 2 months. Armed with spares I replaced them only to have the same results. I complained and they took back the remaining tubes and replaced them with ones that at least had the manufactures name on the lamps. I was also told just to try the 10K and forget the actinic. These replacements did not fall apart and were much whiter but also much dimmer than the first sets. It really made me wonder what all the fuss was about.

First impressions stick with one a long time especially if they are bad. So it still is with PC's although the ones I currently use are much better than those first ones. I'm still wondering when they will have a true 03 actinic as they don't compare to the T-12 nor the T-5 I have now seen.

Anyhow, are PC justified? Well they are certainly a step up from N.O. T-12. As you can see in the graph in the earlier post they are brighter than VHO but only to a limited extent. IMO their best use is in small tanks where the T-12 VHO is just too big to comfortably used. They also are good for unusually shaped tanks. They are not a challenge for MH if you need high PAR under the light. Be assured you can keep most critters, if not all, under PC. The higher K combination lamps available today are vast improvements in both output and color than those available just a few years ago. As I said, I did considerable research into T-5 (much more than when PC first came out) and I think the T-5 will slowly supplant the PC in most applications.

Originally posted by fishboysv
People new to the hobby come here for advice, not abuse from some jerk who probably asked the same questions when he started out.

So you happy fishboy? Yeah I made some Newbie mistakes myself. I won't even talk about my trials and tribulations with host anemones, which always ended up as ghost anemones when I tried to keep them some 18 years ago.

I wasn't planning on talking about PC's till tomorrow--Oh well, till next time.

[WaterKeeper]

Well, let’s move it out here troopers before that Jarhead, Ebacon, finds out I’ve been taking pot shots at his PC lights. You know how it goes E, “One shot, One kill� and another one bites the dust. Any flyboys out there I can harass?

There is nothing wrong with PC lighting. It is just not my own first choice for tanks over 30 gallons. Many, many reefers with large tanks do use it with great results.

Let’s take a second here and explore what lights need to do:
[list=1][*]They must allow the critters we keep to “Live long and prosper�[*]They must illuminate as much of the tank as possible[*]They must not overstep one’s budget[*]They must be pleasing in the eye of the beholder[/list=1]

What? No, being able to light your tennis court just from the glare of your lights shining out the back window is not a consideration.

When we move creatures into our tank from the depths of the ocean we start right off violating the Prime Directive of non-interference. Our main objective is to allow the specimens we keep to live a full life and to hopefully grow and reproduce. Our lighting therefore must be bright enough, and bright in those portions of the spectrum, that are needed to sustain those specimens if we are to adhere to the principles of item 1. Having lights that are very bright but unbalanced in K value can cause even a well illuminated tank to decline. A FO tank with LR need only minimal lighting where a tank housing clams needs, not only high illumination, but illumination in those ranges where the symbiotic alga in that clam can photosynthesis and produce nutrients.

Item two on the list deals with the type of lights and the reflectors in use. A fluorescent evenly covers most of the tank. An MH with a poor reflector only covers a portion of the tank and creates deep shadow areas, a major drawback if your plan is to have a tank with wall to wall corals. Proper reflector choice is very important in lighting our tank.

Item 3 centers on not biting off more that you can chew. It is tax refund time and with a big chunk of change there is a tendency to buy a great big tank with the windfall. There may even be enough left to buy good lights. Six months from now, having spent that cash, there may be the choice of keeping those lights running or switching from steak to frozen pot pies. Initial cost is only the tip of the iceberg. Bulb replacement for larger tanks can be a drain on the wallet. Right now electric costs are high and since fuel cost are intertwined will probably go higher as gasoline prices soar. A 150 gallon tank with lights that produce 6 watts per gallon costs almost $4.00 a week to light around here. It is even higher is some areas. Take that into consideration; especially you draft dodging college punks, when choosing a tank. I hate to see college kids not have money left for their beer.


There is some good news in this area. Light bulbs last much longer these days. Back in the good old days, when I still had teeth, it was pretty much routine to re-bulb about every 6 months. Today any type light worth its salt (water) will last at least a year and in many cases now around 18 months. T-5 has not been around long enough to prove the hype but there are claims they may last over two years. This longevity takes a major cost factor out of the picture.


Item 4 is all about personal preference. I like a tank that is bright and provides true color rendition. Others prefer the “blue� look and op for high K lamps. You want your tank to look good but not at the expense of violating the objective of item 1. Having an anemic looking tank illuminated solely with 50K MH may be attractive to some but harmful to the tank’s inhabitants. If you can, look at other tanks when deciding on a lighting scheme. There are pictures on RC showing different lights on the same tank. This is not the same as seeing those lights in the real world. Computer monitors differ and the beautiful color seen on the screen may not be the same when viewed in real life.

If you follow the above guidelines almost any type lights can be used if proper selections are made.

The old hat, T-12 VHO is a case in point. They were in the early days of reefing a standard for judging lighting. In the days before actinic and brighter lighting even keeping coralline alive was a challenge. VHO changed all that. They still have a lot going for them. They provide very even illumination, they cover the tank without creating sharp shadows, ballasts are small, magnetic ballasts are cheap, high K lights produce more light per watt than in the past, there is little color shift these days and they now last longer. Sure they are old hat but they still are one of the better ways to light any tank greater than 30 gallons in size and having a depth of 2 feet or under. Electronic ballast eliminate flicker, objectionable to some and if you want “glitter/shimmer� lines just mount a clear 20 watt incandescent in the canopy.

Next the care and feeding of MH.

Authors Note-I had a typo in this thread that said the lighting on the 150 gal. tank would cost $4.00/day rather than $4.00/week. I am terribly sorry to anyone whose spouse, who was recently informed there wasn't enough cash for that European vacation you had been planning, took a baseball bat to your tank after seeing the lights cost $4.00/day to run. I am deeply sorry for any inconvenience that may have caused and have since corrected the typo.