Arachnidacolyte said:
Now you tell me. I was wondering why my fish had such big bellies.
I'll get to MH lighting in the next day or two.
So you got a new fish tank Newbie
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Now you tell me. I was wondering why my fish had such big bellies.
I'll get to MH lighting in the next day or two.
Gentle Reader,
I see from my 11/10 posting that I'm supposed to discuss MH in a couple of days. I'm really sorry but my mind is slipping fast and I forgot all about it. Now mental health is something that eludes most serious reefers. Just a glimpse through the manic-depressive ranting in any RC forum proves the point. My own meandering posts are a symptom of the paranoia that is so common to this hobby.
Whoops--just saw in my post above and that is MH LIGHTING I want to talk about.
Never mind.
Ok, the heavy metal of reef tank lighting is Metal Halide lighting. These little babies pack in some serious lighting wallop in a small space. Now metal halide has been around for awhile. Also know as HID (high intensity discharge) lamps; they probably caught on with the type of reefers that grow plants in their basement. :smokin: Actually, in a less romantic vain they were developed for film projector lamps and and billboard lighting, amongst other uses.
In the earlier days of reefing MH bulbs where available with higher K values sooner than VHO, probably because their intended use required a whiter light than florescent. If you wanted bright, high K lighting then MH was the way to go. This benefit of a bright light source in a compact area still makes them popular.
Fluorescent lights spread their illumination in a even fashion along the entire length of the tube. Metal halides provide a point source of intense illumination from a single location, similar to the sun. Higher K MH bulbs still appear to be whiter/bluer than VHO bulbs of similar K values, mainly due to limitations in the phospors. Because they are a point source, they produce diffraction bands, glimmer/glitter lines, when the light passes through ripples on the surface of the tank. Probably their only drawback is they get very hot. I've been informed by people who know more about lighting than I that this is something of an illusion. Just like fluorescent spread the light over a wide area they do the same with the heat they produce. This makes them seem cooler watt for watt although they produce almost the same heat as an MH. I'm also told that the brilliance of MH vs. VHO is apparent because the point source appears brighter than the spread out light pattern of VHO.
All this adds up to the fact that choosing fluorescent over MH is more a matter of preference than actual benefit of one type of illumination over the other.
People with all VHO lighting successfully keep many of the same corals as those with all MH. That is why fence straddlers, like me, use a mix of both.
Now MH lights come in two main flavors. The first is the single ended or mogul base. These use a screw-in socket like an incandescent lamp. These lamps have a bulb within a bulb design. The inner bulb is the actual light and the outer bulb serves as a heat an UV shield. The other type is the double ended or HQI (high quartz iodide) bulb. These bulbs are more like a fluorescent having connectors at each end and they don't have a outter shield like the single ended.
Very Important!!! MH bulbs emit short wave UV radiation. Looking at an unshielded bulb can cause severe eye damage. Exposure of bare skin to some unshielded bulb for a prolonged period can cause burns.
I don't mean to scare you but I do want you to realize there is some danger involved in using MH, especially the the double ended that don't have a shield. It is important to note also that lime soda glass is an effective barrier to short wavelength UV radiation while high quartz glass is not. Plastic, unless specially coated, is also UV transparent. When using MH always have proper shielding on the hood.
What's that? No, suntan lotion is not a good idea in your tank. It overworks the skimmer
Now, just like a florescent, MH lights need a ballast to run. It serves the same purpose as a florescent ballast, that is, to provide the initial kick to start the bulb and to limit the current flowing to the bulb once it lights. In MH ballasts there are two types of starters. The first is a probe start ballast. Lamps that use this type ballast have a third filament in the lamp that is used to initially start the lamp. The second type is called a pulse start. Here the ballast provides a high energy pulse when first turned on to ignite the lamp then drops down to the operating current after ignition. One needs to make sure that the lamps you buy are the same type your ballast will run. These ballasts also come in magnetic and electronic varieties. The electronic in some cases will run either type of starting systems. They are also more compact than their rather bulky magnetic brethren.
I'm out of time for today but we'll finish up with MH and discuss how we go about mounting our lights next time, which I promise won't take 3 weeks.
I see from my 11/10 posting that I'm supposed to discuss MH in a couple of days. I'm really sorry but my mind is slipping fast and I forgot all about it. Now mental health is something that eludes most serious reefers. Just a glimpse through the manic-depressive ranting in any RC forum proves the point. My own meandering posts are a symptom of the paranoia that is so common to this hobby.
Whoops--just saw in my post above and that is MH LIGHTING I want to talk about.
Never mind.
Ok, the heavy metal of reef tank lighting is Metal Halide lighting. These little babies pack in some serious lighting wallop in a small space. Now metal halide has been around for awhile. Also know as HID (high intensity discharge) lamps; they probably caught on with the type of reefers that grow plants in their basement. :smokin: Actually, in a less romantic vain they were developed for film projector lamps and and billboard lighting, amongst other uses.
In the earlier days of reefing MH bulbs where available with higher K values sooner than VHO, probably because their intended use required a whiter light than florescent. If you wanted bright, high K lighting then MH was the way to go. This benefit of a bright light source in a compact area still makes them popular.
Fluorescent lights spread their illumination in a even fashion along the entire length of the tube. Metal halides provide a point source of intense illumination from a single location, similar to the sun. Higher K MH bulbs still appear to be whiter/bluer than VHO bulbs of similar K values, mainly due to limitations in the phospors. Because they are a point source, they produce diffraction bands, glimmer/glitter lines, when the light passes through ripples on the surface of the tank. Probably their only drawback is they get very hot. I've been informed by people who know more about lighting than I that this is something of an illusion. Just like fluorescent spread the light over a wide area they do the same with the heat they produce. This makes them seem cooler watt for watt although they produce almost the same heat as an MH. I'm also told that the brilliance of MH vs. VHO is apparent because the point source appears brighter than the spread out light pattern of VHO.
All this adds up to the fact that choosing fluorescent over MH is more a matter of preference than actual benefit of one type of illumination over the other.
People with all VHO lighting successfully keep many of the same corals as those with all MH. That is why fence straddlers, like me
, use a mix of both.Now MH lights come in two main flavors. The first is the single ended or mogul base. These use a screw-in socket like an incandescent lamp. These lamps have a bulb within a bulb design. The inner bulb is the actual light and the outer bulb serves as a heat an UV shield. The other type is the double ended or HQI (high quartz iodide) bulb. These bulbs are more like a fluorescent having connectors at each end and they don't have a outter shield like the single ended.
Very Important!!! MH bulbs emit short wave UV radiation. Looking at an unshielded bulb can cause severe eye damage. Exposure of bare skin to some unshielded bulb for a prolonged period can cause burns.
I don't mean to scare you but I do want you to realize there is some danger involved in using MH, especially the the double ended that don't have a shield. It is important to note also that lime soda glass is an effective barrier to short wavelength UV radiation while high quartz glass is not. Plastic, unless specially coated, is also UV transparent. When using MH always have proper shielding on the hood.
What's that? No, suntan lotion is not a good idea in your tank. It overworks the skimmer
Now, just like a florescent, MH lights need a ballast to run. It serves the same purpose as a florescent ballast, that is, to provide the initial kick to start the bulb and to limit the current flowing to the bulb once it lights. In MH ballasts there are two types of starters. The first is a probe start ballast. Lamps that use this type ballast have a third filament in the lamp that is used to initially start the lamp. The second type is called a pulse start. Here the ballast provides a high energy pulse when first turned on to ignite the lamp then drops down to the operating current after ignition. One needs to make sure that the lamps you buy are the same type your ballast will run. These ballasts also come in magnetic and electronic varieties. The electronic in some cases will run either type of starting systems. They are also more compact than their rather bulky magnetic brethren.
I'm out of time for today but we'll finish up with MH and discuss how we go about mounting our lights next time, which I promise won't take 3 weeks.
Well I know someone will ask about it so---No, I have no idea on how many watts per fish those glow-in-the-dark zebra fish put out.
Anyhow back to MH. I was talking about ballasts and the pulse start vs. probe start. The double ended bulbs, HQI, also have ballasts specifically designed to run them. J.R., aka electic130, was not shot so bad on Dallas that he couldn't provide some info on MH ballasts. Here is a link to his thread on the subject--MH Ballasts.
It is also handy to see some comparison pictures Joe, JB NY, has a nice series of pics in his thread MH comparison pictures
Both of the above threads provide a wealth of information on MH lighting and humble my attempts to shed light on this complex subject.
As with fluorescent, I strongly recommend that your ballasts be remotely located from your hood. If you use a magnetic ballast with MH you probably have no choice as they are much bigger than fluorescent ballasts. The electronic type can be in a hood but they do give off some heat and they are also easy prey for humidity damaging them in that location.
A couple of things if your are making your own hood. Fluorescents can be mounted just above the water surface. Because they get so hot, you need to have some standoff distance for MH. This is usually about 8" from the water surface. This need to have a standoff distance between the bulbs and the water does have some effect on using MH. Try this. Take a flashlight and take about two steps back from the wall and shine the flashlight on it, observing the beam size. Now take another two steps back and observe the increase in the size of the beam. If you measured it you would find that it covers four times the area even though the distance only doubled. Also, since the flashlight didn't increase its brightness the amount of light per unit area is only a forth of what is was. This distance effect is an important consideration in any tank lighting scheme.
If your hood is wood or plastic you want some space between the hood and bulb or you may start a fire. Having a little fireproof insulation between the hood and reflector is not a bad idea.
It is usually a good idea with VHO, but a must with MH, to include some cooling fans into a MH hood. Most places that sell ballasts will have fans or you can buy the type that are used on computers. They are low cost and fairly reliable. For the latter you'll need a 12 volt power supply to run them.
Having a good reflector is also important. To get the most light energy into your tank a quality reflector is worth the extra few bucks. Reflectors come in two distinct varieties depending on what you want to do. If you savor the very directional light you get from MH then a polished aluminum type is best. On the other hand, if you like a more diffuse light, a white mat reflector is what you need. Again, if you check around the Lighting and DIY forums you will find info on reflector materials and design.
Next installment we have VHO vs. MH in a battle to the death.:hammer:
Anyhow back to MH. I was talking about ballasts and the pulse start vs. probe start. The double ended bulbs, HQI, also have ballasts specifically designed to run them. J.R., aka electic130, was not shot so bad on Dallas that he couldn't provide some info on MH ballasts. Here is a link to his thread on the subject--MH Ballasts.
It is also handy to see some comparison pictures Joe, JB NY, has a nice series of pics in his thread MH comparison pictures
Both of the above threads provide a wealth of information on MH lighting and humble my attempts to shed light on this complex subject.
As with fluorescent, I strongly recommend that your ballasts be remotely located from your hood. If you use a magnetic ballast with MH you probably have no choice as they are much bigger than fluorescent ballasts. The electronic type can be in a hood but they do give off some heat and they are also easy prey for humidity damaging them in that location.
A couple of things if your are making your own hood. Fluorescents can be mounted just above the water surface. Because they get so hot, you need to have some standoff distance for MH. This is usually about 8" from the water surface. This need to have a standoff distance between the bulbs and the water does have some effect on using MH. Try this. Take a flashlight and take about two steps back from the wall and shine the flashlight on it, observing the beam size. Now take another two steps back and observe the increase in the size of the beam. If you measured it you would find that it covers four times the area even though the distance only doubled. Also, since the flashlight didn't increase its brightness the amount of light per unit area is only a forth of what is was. This distance effect is an important consideration in any tank lighting scheme.
If your hood is wood or plastic you want some space between the hood and bulb or you may start a fire. Having a little fireproof insulation between the hood and reflector is not a bad idea.
It is usually a good idea with VHO, but a must with MH, to include some cooling fans into a MH hood. Most places that sell ballasts will have fans or you can buy the type that are used on computers. They are low cost and fairly reliable. For the latter you'll need a 12 volt power supply to run them.
Having a good reflector is also important. To get the most light energy into your tank a quality reflector is worth the extra few bucks. Reflectors come in two distinct varieties depending on what you want to do. If you savor the very directional light you get from MH then a polished aluminum type is best. On the other hand, if you like a more diffuse light, a white mat reflector is what you need. Again, if you check around the Lighting and DIY forums you will find info on reflector materials and design.
Next installment we have VHO vs. MH in a battle to the death.:hammer:
Radicaljbr
Active member
Have you ever thought about writing a book? Or have you already done so? You are truly filled with great knowledge.
thanks for the info
John
thanks for the info
John
Radicaljbr
Active member
I just got done reading this entire posting, how wonderful!! I do have a question if I may. I have a 105 gallon tank, which is 29" tall. I have PC lighting which includes 2- 65 watt Actinicand 2-10,000K 65 watts. This is what my LFS told I needed and that it was all I needed for a reef tank. But, your saying if I want to put anenomes in it, which I do, I will need about 840 watts. If I am adding this right, I have 260 watts. So I really need to buy 2 more of these PC? Then I would have 3 lighing housing units, I can not fit 3 in there. How would I do this?
thanks again for all your great info.
John
thanks again for all your great info.
John
I too just got finished reading this entire thread and all of its links, and I'm truly amazed. While I'm just a week or so into my initial research and am in the "plan before I buy" stage, I just learned more in the past hour than I have in the past week. I'm looking at a 90 gal with 140# of live sand, 90# of live rock, and seeded water. I want a reef tank but am just starting my research on the different types of corals, etc. The LFS wants to put 4x110W VHO (2 white, 2 blue). The formula would tell me this is insufficient. I'd like to avoid having to go to metal halides thought. What's the verdict? Is a 5x110W feasible or would that not usually fit in a canopy for a 90 gal?
bluefossil
New member
WaterKeeper said:
Can you also include T-5 in the battle royale too? :rollface:
Hi wsg
<img src="/images/welcome.gif" width="500" height="62"><br><b><i><big><big>To Reef Central</b></i></big></big>
And I'm glad so many of you enjoy this thread.
John,
Currently there is some debate over on the Team RC forum about light and anemones. I have never been successful with anemones myself and always attributed my failure in keeping them to insufficient lighting. However, there are people that say they have maintained them with as little as 4 watts per gallon. The debate is still raging and eventually there is supposed to be a FAQ out on anemones. The wheels of TRC move exceedingly slow; as does the WaterKeeper..
I do feel that anemones are a poor choice for the new reefer. It is best to get a little experience under ones belt, as they are very fragile critters. Also, one dying in your tank can be a very bad experience as there is usually a very large ammonia spike following ones demise. They can nuke the entire tank.
With the PC lights you should be able to squeeze in more bulbs into the hood, as they don't take up that much room. You do need to do some wiring but it is not that hard. Also, you might consider going to a 96 watt lamp if you can handle the 33.5" length.
yz,
Same in your case, with a little creative wiring you can add an additional VHO. Unless you plan on keeping critters than require the higher lighting you may be fine with what you have.
bluefossil,
T-5 is fluorescent lighting, just a thinner tube. It is currently only available in HO but I hear VHO is soon to show up.
And all of you want to check out the lighting forum on any lighting plan. This thread just scratches the surface.
I have to go X-mas shopping this afternoon but I'll try to get more into this thread before Santa arrives.
<img src="/images/welcome.gif" width="500" height="62"><br><b><i><big><big>To Reef Central</b></i></big></big>
And I'm glad so many of you enjoy this thread.
John,
Currently there is some debate over on the Team RC forum about light and anemones. I have never been successful with anemones myself and always attributed my failure in keeping them to insufficient lighting. However, there are people that say they have maintained them with as little as 4 watts per gallon. The debate is still raging and eventually there is supposed to be a FAQ out on anemones. The wheels of TRC move exceedingly slow; as does the WaterKeeper..
I do feel that anemones are a poor choice for the new reefer. It is best to get a little experience under ones belt, as they are very fragile critters. Also, one dying in your tank can be a very bad experience as there is usually a very large ammonia spike following ones demise. They can nuke the entire tank.
With the PC lights you should be able to squeeze in more bulbs into the hood, as they don't take up that much room. You do need to do some wiring but it is not that hard. Also, you might consider going to a 96 watt lamp if you can handle the 33.5" length.
yz,
Same in your case, with a little creative wiring you can add an additional VHO. Unless you plan on keeping critters than require the higher lighting you may be fine with what you have.
bluefossil,
T-5 is fluorescent lighting, just a thinner tube. It is currently only available in HO but I hear VHO is soon to show up.
And all of you want to check out the lighting forum on any lighting plan. This thread just scratches the surface.
I have to go X-mas shopping this afternoon but I'll try to get more into this thread before Santa arrives.
dbroome,
Its those darned elves in the gift wrap department. They're soooo slow.
Actually, as in any thread on lighting, I had to make a table to show how VHO and MH match up. It took all my time over the holidays to make it.
Table 1
Its those darned elves in the gift wrap department. They're soooo slow.
Actually, as in any thread on lighting, I had to make a table to show how VHO and MH match up. It took all my time over the holidays to make it.
Table 1
Radicaljbr
Active member
Great table!! I too live in Ohio, but in the NE. Our grass here is covered by this white stuff that fell from the sky. Any way to clear it up? It is kind of like my milky white clouded tank right now.
John
John
I export the nitrates and phosphates from my tank out to the grass and don't add as much KW as you in Northern Ohio.
I tried to post this continuation on the lighting yesterday but after the lame table joke RC banned me from posting the rest of the day. Here goes--
Heck Newbie, How do you ever expect to keep a reef tank without MH lighting? Or, MH light will bleach your corals and theyââ"šÂ¬Ã¢"žÂ¢ll all die!
Sound familiar. You bet. All as I can say is---
HOGWASH!!!!!
There are thousands of reefers out there that have very nice tanks without any MH. Some even keep clams under VHO. People with about a zillion watts per gallon of MH lights have beautiful tanks of coral.
As often happens newer technology often gets elevated to such a status that older technology is swept to the wayside. This is most unfortunate as sometimes the newest technology only offers marginal improvement over the old. IMO this is true of MH vs. fluorescent lighting. Both can serve the same purpose, either alone, or in concert with each other.
Claims for MH say it is much more intense but in reality this is more of a visual illusion. When you compare overall output per watt of MH to VHO there is not that great of a difference. MH bulbs are a point source and appear brighter than the diffuse effect from a fluorescent tube. Also, as MH bulbs need to be mounted further from the water surface any extra intensity is offset by the standoff height.
MH bulbs last longer than fluorescent is another claim. Not so much these days as improved phosphors have made most fluorescents have about a year of useful life. MH bulbs age too. The process is somewhat different as some of the internal filament is sputtered off and then condenses on the relatively cooler quartz tube. This reduces output and changes spectral output. Again, improvements have been made in MH design and they too can last a year or more.
Spectral output of the two varies with K value and can differ greatly from bulb to bulb. If you go to the Sylvania-Osram site they have graphs of the spectral output of all their bulbs and they tend to keep them updated. If you notice in their graphs, a 6500K daylight fluorescent has a spectrum which covers almost the entire visible light range. This is not a special aquarium bulb but a normal daylight fluorescent.
One of the problems with making tables of bulb outputs and spectra is that it changes with time. Advances in the bulbs make any data over a year old someone outdated. Also, very few people that compare bulbs do so with bulbs that have been run a month or two. A bulb that shows superior output when brand new may have mediocre output a few months later.
An argument for fluorescents is that they are cooler than MH. However, just like MH appear brighter than VHO because they are a point source, they also appear hotter for the same reason. The VHO just spreads the heat out over a large area.
I don't have the resources to buy a bunch of bulbs and test them all in proper fashion. Also, such data would be quickly dated. Therefore, at the risk of being told it has no scientific value, I declare there is no clear winner. A good tank can be maintained with either.
What is important is having enough light and placing your most light hungry creatures closest to it. I myself use a combination of MH and VHO in larger tanks and use straight fluorescent, either PC or VHO, on smaller tanks. T-5 would be satisfactory here as well.
Boy, how is that for a cop out.
Oh, one more word on heat for you people that plan a tank with lighting that will eliminate the need for street lights around your home. Tanks up to around 150 gallons and running up to 8 watts per gallon can usually get by without a chiller. Tanks over 150 have less external surface area to water volume and don't radiate heat to the atmosphere as fast. So the bigger the tank the more likelihood you will need a chiller. A major cost consideration in any lighting decision.
Well thatââ"šÂ¬Ã¢"žÂ¢s it for today. Iââ"šÂ¬Ã¢"žÂ¢ll wrap up lighting REAL soon.
I tried to post this continuation on the lighting yesterday but after the lame table joke RC banned me from posting the rest of the day. Here goes--
Heck Newbie, How do you ever expect to keep a reef tank without MH lighting? Or, MH light will bleach your corals and theyââ"šÂ¬Ã¢"žÂ¢ll all die!
Sound familiar. You bet. All as I can say is---
HOGWASH!!!!!
There are thousands of reefers out there that have very nice tanks without any MH. Some even keep clams under VHO. People with about a zillion watts per gallon of MH lights have beautiful tanks of coral.
As often happens newer technology often gets elevated to such a status that older technology is swept to the wayside. This is most unfortunate as sometimes the newest technology only offers marginal improvement over the old. IMO this is true of MH vs. fluorescent lighting. Both can serve the same purpose, either alone, or in concert with each other.
Claims for MH say it is much more intense but in reality this is more of a visual illusion. When you compare overall output per watt of MH to VHO there is not that great of a difference. MH bulbs are a point source and appear brighter than the diffuse effect from a fluorescent tube. Also, as MH bulbs need to be mounted further from the water surface any extra intensity is offset by the standoff height.
MH bulbs last longer than fluorescent is another claim. Not so much these days as improved phosphors have made most fluorescents have about a year of useful life. MH bulbs age too. The process is somewhat different as some of the internal filament is sputtered off and then condenses on the relatively cooler quartz tube. This reduces output and changes spectral output. Again, improvements have been made in MH design and they too can last a year or more.
Spectral output of the two varies with K value and can differ greatly from bulb to bulb. If you go to the Sylvania-Osram site they have graphs of the spectral output of all their bulbs and they tend to keep them updated. If you notice in their graphs, a 6500K daylight fluorescent has a spectrum which covers almost the entire visible light range. This is not a special aquarium bulb but a normal daylight fluorescent.
One of the problems with making tables of bulb outputs and spectra is that it changes with time. Advances in the bulbs make any data over a year old someone outdated. Also, very few people that compare bulbs do so with bulbs that have been run a month or two. A bulb that shows superior output when brand new may have mediocre output a few months later.
An argument for fluorescents is that they are cooler than MH. However, just like MH appear brighter than VHO because they are a point source, they also appear hotter for the same reason. The VHO just spreads the heat out over a large area.
I don't have the resources to buy a bunch of bulbs and test them all in proper fashion. Also, such data would be quickly dated. Therefore, at the risk of being told it has no scientific value, I declare there is no clear winner. A good tank can be maintained with either.
What is important is having enough light and placing your most light hungry creatures closest to it. I myself use a combination of MH and VHO in larger tanks and use straight fluorescent, either PC or VHO, on smaller tanks. T-5 would be satisfactory here as well.
Boy, how is that for a cop out.
Oh, one more word on heat for you people that plan a tank with lighting that will eliminate the need for street lights around your home. Tanks up to around 150 gallons and running up to 8 watts per gallon can usually get by without a chiller. Tanks over 150 have less external surface area to water volume and don't radiate heat to the atmosphere as fast. So the bigger the tank the more likelihood you will need a chiller. A major cost consideration in any lighting decision.
Well thatââ"šÂ¬Ã¢"žÂ¢s it for today. Iââ"šÂ¬Ã¢"žÂ¢ll wrap up lighting REAL soon.
Hi FLpatty
Not really Patty. RC is switching servers and it poses a threat to the Empire. They keep attacking from cyberspace and it sometimes causes a divergence in the Force. During those attacks you may get the dread "Server Timed Out" or similar message. As a good Padawan learner you must be patient and post latter in the space-time continuum.:strooper:
Not really Patty. RC is switching servers and it poses a threat to the Empire. They keep attacking from cyberspace and it sometimes causes a divergence in the Force. During those attacks you may get the dread "Server Timed Out" or similar message. As a good Padawan learner you must be patient and post latter in the space-time continuum.:strooper:
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