t5's vs metal halide?
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mr_x
Active Member
i believe the heat coming off of t-5's is just dispersed over a long bulb. if you take the equivelant (150 watts of t-5, versus 150 watts of halide, it will give off the same heat.
t-5's seem cooler because you can put a less wattage fixture over your tank and achieve the same dispersment of light it would take 2 halides to do.
i never used any sort of testing equiptment to come to this conclusion, just have both t-5 fixtures and halides.
t-5's seem cooler because you can put a less wattage fixture over your tank and achieve the same dispersment of light it would take 2 halides to do.
i never used any sort of testing equiptment to come to this conclusion, just have both t-5 fixtures and halides.
muggiwhplar
Member
Originally Posted by Mr_X
http:///forum/post/2649978
i believe the heat coming off of t-5's is just dispersed over a long bulb. if you take the equivelant (150 watts of t-5, versus 150 watts of halide, it will give off the same heat.
t-5's seem cooler because you can put a less wattage fixture over your tank and achieve the same dispersment of light it would take 2 halides to do.
i never used any sort of testing equiptment to come to this conclusion, just have both t-5 fixtures and halides.
I've been looking at changing my lighting system lately--initially just improving the reflectors on my halides, but now considering switching to T5's. The reason for the switch is that the argument you're making here would make sense if our halides and T5s had similar luminous efficacies--but all the information I'm finding indicates that there is a considerable difference. From what I've read, a typical T5 will put out around 90 - 95 lumens/watt. While the most efficient halides can give off as much as 120 or 140 lumens/watt, the ones most of us use on our aquariums are about half as productive. So, my 2X250W metal halides are probably only giving me as much light as 340W of T5 lighting. That's an additional 160W of heat being radiated away, at least partially into my tank.
http:///forum/post/2649978
i believe the heat coming off of t-5's is just dispersed over a long bulb. if you take the equivelant (150 watts of t-5, versus 150 watts of halide, it will give off the same heat.
t-5's seem cooler because you can put a less wattage fixture over your tank and achieve the same dispersment of light it would take 2 halides to do.
i never used any sort of testing equiptment to come to this conclusion, just have both t-5 fixtures and halides.
I've been looking at changing my lighting system lately--initially just improving the reflectors on my halides, but now considering switching to T5's. The reason for the switch is that the argument you're making here would make sense if our halides and T5s had similar luminous efficacies--but all the information I'm finding indicates that there is a considerable difference. From what I've read, a typical T5 will put out around 90 - 95 lumens/watt. While the most efficient halides can give off as much as 120 or 140 lumens/watt, the ones most of us use on our aquariums are about half as productive. So, my 2X250W metal halides are probably only giving me as much light as 340W of T5 lighting. That's an additional 160W of heat being radiated away, at least partially into my tank.
chilwil84
Active Member
my t5s def raise my tanks temp a few degrees. they keep my tank in the low 80s(with house being in the 70s). its a 40 breeder with 6 bulb individual reflected t5s, along with another 20 gallons in my refugium. i run a fan on the fuge when lights are on and a fan drawing air away from the reflectors when the lights are on. unless ur running a 400 mh on a cube the heat really isnt that much different.
muggiwhplar
Member
Originally Posted by Hurt
http:///forum/post/2650924
What Mr. X said^. There is no difference in heat output between the MH and T-5. Watts are Watts. MH's though are more efficient than T-5's(lumens/watts) and of course they penetrate the water deeper.
Google: The Myth of MH being hotter than T5s
You're right that watts are watts, but there is a difference in the amount of watts converted to light vs. heat for the two light types. As I said in my previous post, the stuff I've been reading seems to indicate that T5's will give you substantially more light per watt than metal halides--which means that the halides are giving you less light and more heat. If you have a reputable source saying otherwise, I'd be interested to read it. I don't mean for that to sound argumentative--I would be genuinely interested in any info you have.
http:///forum/post/2650924
What Mr. X said^. There is no difference in heat output between the MH and T-5. Watts are Watts. MH's though are more efficient than T-5's(lumens/watts) and of course they penetrate the water deeper.
Google: The Myth of MH being hotter than T5s
You're right that watts are watts, but there is a difference in the amount of watts converted to light vs. heat for the two light types. As I said in my previous post, the stuff I've been reading seems to indicate that T5's will give you substantially more light per watt than metal halides--which means that the halides are giving you less light and more heat. If you have a reputable source saying otherwise, I'd be interested to read it. I don't mean for that to sound argumentative--I would be genuinely interested in any info you have.
hurt
Active Member
Originally Posted by muggiwhplar
http:///forum/post/2651035
You're right that watts are watts, but there is a difference in the amount of watts converted to light vs. heat for the two light types. As I said in my previous post, the stuff I've been reading seems to indicate that T5's will give you substantially more light per watt than metal halides--which means that the halides are giving you less light and more heat. If you have a reputable source saying otherwise, I'd be interested to read it. I don't mean for that to sound argumentative--I would be genuinely interested in any info you have.
Have you googled what I said ^...there is over 15 pages of info on the subject.
http:///forum/post/2651035
You're right that watts are watts, but there is a difference in the amount of watts converted to light vs. heat for the two light types. As I said in my previous post, the stuff I've been reading seems to indicate that T5's will give you substantially more light per watt than metal halides--which means that the halides are giving you less light and more heat. If you have a reputable source saying otherwise, I'd be interested to read it. I don't mean for that to sound argumentative--I would be genuinely interested in any info you have.
Have you googled what I said ^...there is over 15 pages of info on the subject.
muggiwhplar
Member
Originally Posted by Hurt
http:///forum/post/2651062
Have you googled what I said ^...there is over 15 pages of info on the subject.
Yes, and although I didn't read every single page in its entirety, I skimmed a bunch and didn't see any reference to solid data showing that the metal halides we use have a higher luminous efficacy than T5's. When I look up "T5 vs metal halide efficacy", I find things like this. From what I've gathered by reading, there are some metal halides that will out-perform T5's, but the ones we typically use on our aquariums put out 60 - 70 lumens/watt.
http:///forum/post/2651062
Have you googled what I said ^...there is over 15 pages of info on the subject.
Yes, and although I didn't read every single page in its entirety, I skimmed a bunch and didn't see any reference to solid data showing that the metal halides we use have a higher luminous efficacy than T5's. When I look up "T5 vs metal halide efficacy", I find things like this. From what I've gathered by reading, there are some metal halides that will out-perform T5's, but the ones we typically use on our aquariums put out 60 - 70 lumens/watt.
hurt
Active Member
Copy and paste:
The basic premise that MH heat a tank more than T5 is busted.
Both types of lamps put out very similar radiant energy. Part of the radiant energy is visible and both types of lamps are nearly even in that regard. They primarily differ in the amount UV and IR that they emit (radiate).
If you take a look at the electromagnetic spectrum you will see that IR is the the Left of Visible light and UV to the Right. Microwave (think about it) is far to the Left and X-Ray and Gamma Rays are far to the right. Would you care to guess which (IR or UV is more readily absorbed (turned to heat) by a mass. Apply your choice to the chart that I posted
The T5 is 21% visible and Metal Halide is 27% visible. Pretty close.
The T5 puts out 37% IR, that is readily absorbed (converted to heat) by the mass in the tank (including the water) as heat.
The MH Puts out 17% IR and 19% UV.
We can look at the overal visible spectral peaks and make some assumptions about the wavelengths more likely to be absorbed.. but it is kind of pointless at this level. Instead we will just assume that 50% of the visible spectrum is close to the UV and and the other 50% close to the IR end. So 11% for the T5 and 14% for the MH.
So lets add it up.. (purists, please don't go bonkers.. this is just a rough idea of what is going on). 48% for the T5 and 33% for the MH. To be nice we will include some of the UV for the halide, lets say 9%. That is 48% vs 42%. It still certainly looks like the energy from the halide has less of a chance of being absorbed in the tank. Of course you could fiddle with the numbers and come up with any number of conclusions.
The point is that both fixtures are fairly similar and that the MYTH that T5 put less heat into the tank is pretty much busted at least in terms of radiant energy.
The variables are in the actual setups and have a lot to do with air movement and other factors.
Bottom line: (the same as it was 5 pages back)
With regard to the ROOM, a WATT is a WATT.
With regard to the TANK, there is LITTLE difference between the T5 and MH and in MANY cases the T5 imparts MORE heat into the tank than a MH of similar wattage.
The basic premise that MH heat a tank more than T5 is busted.
Both types of lamps put out very similar radiant energy. Part of the radiant energy is visible and both types of lamps are nearly even in that regard. They primarily differ in the amount UV and IR that they emit (radiate).
If you take a look at the electromagnetic spectrum you will see that IR is the the Left of Visible light and UV to the Right. Microwave (think about it) is far to the Left and X-Ray and Gamma Rays are far to the right. Would you care to guess which (IR or UV is more readily absorbed (turned to heat) by a mass. Apply your choice to the chart that I posted
The T5 is 21% visible and Metal Halide is 27% visible. Pretty close.
The T5 puts out 37% IR, that is readily absorbed (converted to heat) by the mass in the tank (including the water) as heat.
The MH Puts out 17% IR and 19% UV.
We can look at the overal visible spectral peaks and make some assumptions about the wavelengths more likely to be absorbed.. but it is kind of pointless at this level. Instead we will just assume that 50% of the visible spectrum is close to the UV and and the other 50% close to the IR end. So 11% for the T5 and 14% for the MH.
So lets add it up.. (purists, please don't go bonkers.. this is just a rough idea of what is going on). 48% for the T5 and 33% for the MH. To be nice we will include some of the UV for the halide, lets say 9%. That is 48% vs 42%. It still certainly looks like the energy from the halide has less of a chance of being absorbed in the tank. Of course you could fiddle with the numbers and come up with any number of conclusions.
The point is that both fixtures are fairly similar and that the MYTH that T5 put less heat into the tank is pretty much busted at least in terms of radiant energy.
The variables are in the actual setups and have a lot to do with air movement and other factors.
Bottom line: (the same as it was 5 pages back)
With regard to the ROOM, a WATT is a WATT.
With regard to the TANK, there is LITTLE difference between the T5 and MH and in MANY cases the T5 imparts MORE heat into the tank than a MH of similar wattage.
hurt
Active Member
Copy and paste:
"The basic premise that MH heat a tank more than T5 is busted.
Both types of lamps put out very similar radiant energy. Part of the radiant energy is visible and both types of lamps are nearly even in that regard. They primarily differ in the amount UV and IR that they emit (radiate).
If you take a look at the electromagnetic spectrum you will see that IR is the the Left of Visible light and UV to the Right. Microwave (think about it) is far to the Left and X-Ray and Gamma Rays are far to the right. Would you care to guess which (IR or UV is more readily absorbed (turned to heat) by a mass. Apply your choice to the chart that I posted
The T5 is 21% visible and Metal Halide is 27% visible. Pretty close.
The T5 puts out 37% IR, that is readily absorbed (converted to heat) by the mass in the tank (including the water) as heat.
The MH Puts out 17% IR and 19% UV.
We can look at the overal visible spectral peaks and make some assumptions about the wavelengths more likely to be absorbed.. but it is kind of pointless at this level. Instead we will just assume that 50% of the visible spectrum is close to the UV and and the other 50% close to the IR end. So 11% for the T5 and 14% for the MH.
So lets add it up.. (purists, please don't go bonkers.. this is just a rough idea of what is going on). 48% for the T5 and 33% for the MH. To be nice we will include some of the UV for the halide, lets say 9%. That is 48% vs 42%. It still certainly looks like the energy from the halide has less of a chance of being absorbed in the tank. Of course you could fiddle with the numbers and come up with any number of conclusions.
The point is that both fixtures are fairly similar and that the MYTH that T5 put less heat into the tank is pretty much busted at least in terms of radiant energy.
The variables are in the actual setups and have a lot to do with air movement and other factors.
Bottom line: (the same as it was 5 pages back)
With regard to the ROOM, a WATT is a WATT.
With regard to the TANK, there is LITTLE difference between the T5 and MH and in MANY cases the T5 imparts MORE heat into the tank than a MH of similar wattage."
"The basic premise that MH heat a tank more than T5 is busted.
Both types of lamps put out very similar radiant energy. Part of the radiant energy is visible and both types of lamps are nearly even in that regard. They primarily differ in the amount UV and IR that they emit (radiate).
If you take a look at the electromagnetic spectrum you will see that IR is the the Left of Visible light and UV to the Right. Microwave (think about it) is far to the Left and X-Ray and Gamma Rays are far to the right. Would you care to guess which (IR or UV is more readily absorbed (turned to heat) by a mass. Apply your choice to the chart that I posted
The T5 is 21% visible and Metal Halide is 27% visible. Pretty close.
The T5 puts out 37% IR, that is readily absorbed (converted to heat) by the mass in the tank (including the water) as heat.
The MH Puts out 17% IR and 19% UV.
We can look at the overal visible spectral peaks and make some assumptions about the wavelengths more likely to be absorbed.. but it is kind of pointless at this level. Instead we will just assume that 50% of the visible spectrum is close to the UV and and the other 50% close to the IR end. So 11% for the T5 and 14% for the MH.
So lets add it up.. (purists, please don't go bonkers.. this is just a rough idea of what is going on). 48% for the T5 and 33% for the MH. To be nice we will include some of the UV for the halide, lets say 9%. That is 48% vs 42%. It still certainly looks like the energy from the halide has less of a chance of being absorbed in the tank. Of course you could fiddle with the numbers and come up with any number of conclusions.
The point is that both fixtures are fairly similar and that the MYTH that T5 put less heat into the tank is pretty much busted at least in terms of radiant energy.
The variables are in the actual setups and have a lot to do with air movement and other factors.
Bottom line: (the same as it was 5 pages back)
With regard to the ROOM, a WATT is a WATT.
With regard to the TANK, there is LITTLE difference between the T5 and MH and in MANY cases the T5 imparts MORE heat into the tank than a MH of similar wattage."
hurt
Active Member
cont.(copy and paste)
"both the MH and T5 have very similar radiant outputs. The T5 has a higher IR outout, while the MH has a higher UV output. In the end, both types of lamps (if the same wattage) impart roughly the same amount of heat into the water.
The MH and its compact reflector may direct more heat downward into the tank via radiation and convection, while the T5 may have a better chance of radiating and convecting heat into directly into the room, due to the large surface area of the reflector. On the other hand, the T5 fixture will inhibit airflow to a greater extent, trapping more heat between the fixture and the water. This can create an environment where convective heat transfer is greatly increased.
In the end, it simply depends on the setup. If we take (2) 150W halide pendants and compare them to a 300W T5 fixture, the MH will likely heat the water less simply due to the fact that it allows a much greater air flow around the fixture and therefore reduces covective heat transfer to the water (in favor of the room)."
"both the MH and T5 have very similar radiant outputs. The T5 has a higher IR outout, while the MH has a higher UV output. In the end, both types of lamps (if the same wattage) impart roughly the same amount of heat into the water.
The MH and its compact reflector may direct more heat downward into the tank via radiation and convection, while the T5 may have a better chance of radiating and convecting heat into directly into the room, due to the large surface area of the reflector. On the other hand, the T5 fixture will inhibit airflow to a greater extent, trapping more heat between the fixture and the water. This can create an environment where convective heat transfer is greatly increased.
In the end, it simply depends on the setup. If we take (2) 150W halide pendants and compare them to a 300W T5 fixture, the MH will likely heat the water less simply due to the fact that it allows a much greater air flow around the fixture and therefore reduces covective heat transfer to the water (in favor of the room)."
geoj
Active Member
Originally Posted by Hurt
http:///forum/post/2651226
Copy and paste:
The basic premise that MH heat a tank more than T5 is busted.
Both types of lamps put out very similar radiant energy. Part of the radiant energy is visible and both types of lamps are nearly even in that regard. They primarily differ in the amount UV and IR that they emit (radiate).
If you take a look at the electromagnetic spectrum you will see that IR is the the Left of Visible light and UV to the Right. Microwave (think about it) is far to the Left and X-Ray and Gamma Rays are far to the right. Would you care to guess which (IR or UV is more readily absorbed (turned to heat) by a mass. Apply your choice to the chart that I posted
The T5 is 21% visible and Metal Halide is 27% visible. Pretty close.
The T5 puts out 37% IR, that is readily absorbed (converted to heat) by the mass in the tank (including the water) as heat.
The MH Puts out 17% IR and 19% UV.
We can look at the overal visible spectral peaks and make some assumptions about the wavelengths more likely to be absorbed.. but it is kind of pointless at this level. Instead we will just assume that 50% of the visible spectrum is close to the UV and and the other 50% close to the IR end. So 11% for the T5 and 14% for the MH.
So lets add it up.. (purists, please don't go bonkers.. this is just a rough idea of what is going on). 48% for the T5 and 33% for the MH. To be nice we will include some of the UV for the halide, lets say 9%. That is 48% vs 42%. It still certainly looks like the energy from the halide has less of a chance of being absorbed in the tank. Of course you could fiddle with the numbers and come up with any number of conclusions.
The point is that both fixtures are fairly similar and that the MYTH that T5 put less heat into the tank is pretty much busted at least in terms of radiant energy.
The variables are in the actual setups and have a lot to do with air movement and other factors.
Bottom line: (the same as it was 5 pages back)
With regard to the ROOM, a WATT is a WATT.
With regard to the TANK, there is LITTLE difference between the T5 and MH and in MANY cases the T5 imparts MORE heat into the tank than a MH of similar wattage.
You have it wrong! There is no reference to HO T5 in this Source.
Copy and paste:
Source efficacy (2006)
• Incandescent (75W) ~13 lm/W
• Fluorescent (T8) ~83 lm/W
• HID (Metal Halide) ~100 lm/W
• SSL (White LED) ~50 lm/W
Normalized retail lamp price (2006)
• Incandescent (75W) ~0.60 $/klm
• Fluorescent (T8) ~0.73 $/klm
• HID (Metal Halide) ~1.27 $/klm
• SSL (White LED) ~50.00 $/klm
*manufacturer data
Research is improving SSL efficacy while decreasing price
Efficiency and Cost of White-Light Sources
Need I say more!
http:///forum/post/2651226
Copy and paste:
The basic premise that MH heat a tank more than T5 is busted.
Both types of lamps put out very similar radiant energy. Part of the radiant energy is visible and both types of lamps are nearly even in that regard. They primarily differ in the amount UV and IR that they emit (radiate).
If you take a look at the electromagnetic spectrum you will see that IR is the the Left of Visible light and UV to the Right. Microwave (think about it) is far to the Left and X-Ray and Gamma Rays are far to the right. Would you care to guess which (IR or UV is more readily absorbed (turned to heat) by a mass. Apply your choice to the chart that I posted
The T5 is 21% visible and Metal Halide is 27% visible. Pretty close.
The T5 puts out 37% IR, that is readily absorbed (converted to heat) by the mass in the tank (including the water) as heat.
The MH Puts out 17% IR and 19% UV.
We can look at the overal visible spectral peaks and make some assumptions about the wavelengths more likely to be absorbed.. but it is kind of pointless at this level. Instead we will just assume that 50% of the visible spectrum is close to the UV and and the other 50% close to the IR end. So 11% for the T5 and 14% for the MH.
So lets add it up.. (purists, please don't go bonkers.. this is just a rough idea of what is going on). 48% for the T5 and 33% for the MH. To be nice we will include some of the UV for the halide, lets say 9%. That is 48% vs 42%. It still certainly looks like the energy from the halide has less of a chance of being absorbed in the tank. Of course you could fiddle with the numbers and come up with any number of conclusions.
The point is that both fixtures are fairly similar and that the MYTH that T5 put less heat into the tank is pretty much busted at least in terms of radiant energy.
The variables are in the actual setups and have a lot to do with air movement and other factors.
Bottom line: (the same as it was 5 pages back)
With regard to the ROOM, a WATT is a WATT.
With regard to the TANK, there is LITTLE difference between the T5 and MH and in MANY cases the T5 imparts MORE heat into the tank than a MH of similar wattage.
You have it wrong! There is no reference to HO T5 in this Source.
Copy and paste:
Source efficacy (2006)
• Incandescent (75W) ~13 lm/W
• Fluorescent (T8) ~83 lm/W
• HID (Metal Halide) ~100 lm/W
• SSL (White LED) ~50 lm/W
Normalized retail lamp price (2006)
• Incandescent (75W) ~0.60 $/klm
• Fluorescent (T8) ~0.73 $/klm
• HID (Metal Halide) ~1.27 $/klm
• SSL (White LED) ~50.00 $/klm
*manufacturer data
Research is improving SSL efficacy while decreasing price
Efficiency and Cost of White-Light Sources
Need I say more!
hurt
Active Member
Originally Posted by GeoJ
http:///forum/post/2651245
You have it wrong! There is no reference to HO T5 in this Source.
Copy and paste:
Source efficacy (2006)
• Incandescent (75W) ~13 lm/W
• Fluorescent (T8) ~83 lm/W
• HID (Metal Halide) ~100 lm/W
• SSL (White LED) ~50 lm/W
Normalized retail lamp price (2006)
• Incandescent (75W) ~0.60 $/klm
• Fluorescent (T8) ~0.73 $/klm
• HID (Metal Halide) ~1.27 $/klm
• SSL (White LED) ~50.00 $/klm
*manufacturer data
Research is improving SSL efficacy while decreasing price
Efficiency and Cost of White-Light Sources
Need I say more!
Um...actually, I don't have it wrong! If you had read the whole thread you would have seen the following posted. Again this is not my first hand info, this is copy and paste from someone who knows quite a bit about lighting systems.
"There are subtle difference between the different types of fluorescent lighting. Each tube type has a slightly different efficiency rating and characteristics. THe same holds true with different types of Metal Halides. The MAJOR difference between a T5 and a T12 bulb is the tube diameter and the amount of light that can be efficiently redirected via the use of a narrow SLR.
You may wish to know that the T5 HO bulbs are less efficient than the NO versions (the same for T12s. The NO are more efficient than the HO or VHO versions).
T12 NO are in the 85 l/W range
T8 NO are in the 92 l/W range
T5 NO are in the 100 l/W range
T5 HO are in the 93 l/W range.
The D.O.E. CHART above is likely talking about normal output T12 or T8 bulbs. In any case it really does not matter because they are all very similar."
http:///forum/post/2651245
You have it wrong! There is no reference to HO T5 in this Source.
Copy and paste:
Source efficacy (2006)
• Incandescent (75W) ~13 lm/W
• Fluorescent (T8) ~83 lm/W
• HID (Metal Halide) ~100 lm/W
• SSL (White LED) ~50 lm/W
Normalized retail lamp price (2006)
• Incandescent (75W) ~0.60 $/klm
• Fluorescent (T8) ~0.73 $/klm
• HID (Metal Halide) ~1.27 $/klm
• SSL (White LED) ~50.00 $/klm
*manufacturer data
Research is improving SSL efficacy while decreasing price
Efficiency and Cost of White-Light Sources
Need I say more!
Um...actually, I don't have it wrong! If you had read the whole thread you would have seen the following posted. Again this is not my first hand info, this is copy and paste from someone who knows quite a bit about lighting systems.
"There are subtle difference between the different types of fluorescent lighting. Each tube type has a slightly different efficiency rating and characteristics. THe same holds true with different types of Metal Halides. The MAJOR difference between a T5 and a T12 bulb is the tube diameter and the amount of light that can be efficiently redirected via the use of a narrow SLR.
You may wish to know that the T5 HO bulbs are less efficient than the NO versions (the same for T12s. The NO are more efficient than the HO or VHO versions).
T12 NO are in the 85 l/W range
T8 NO are in the 92 l/W range
T5 NO are in the 100 l/W range
T5 HO are in the 93 l/W range.
The D.O.E. CHART above is likely talking about normal output T12 or T8 bulbs. In any case it really does not matter because they are all very similar."
muggiwhplar
Member
There's no need for the attitude there. I haven't attacked you personally; I'm just discussing data I've read regarding aquarium lighting systems, so let's calm down and not take ourselves too seriously. After reading your post, it seemed that we had each found at least somewhat reputable data to back up opposing claims.
As I had mentioned previously, there is considerable variability in the efficacy of different halide lamps, and I wasn't sure whether that DOE data was using a lamp that would be equivalent to what we typically use. So I went to the websites of various bulb manufacturers and looked for spec sheets. Most didn't have any available, but Ushio and Iwasaki did. From what I was able to find on their sites, those bulbs range from about 42 to 72 lumens/watt. On the other hand, according to Current's website, their T5's deliver betwen 95 and 105 lumens/watt. As you pointed out, that energy that isn't being converted into visible light by the halides is either being converted into heat, IR (which for all practical purposes is the same as heat here) or UV (much of which will be converted into heat when it is absorbed by the glass layer between the bulb and the water). At the very least, within the context of our hobby and the equipment we use, it would appear that you can get the same amount of useful light out of a T5 with less energy consumption. Since I couldn't find any data on exactly how much IR and UV the bulbs we use put out, or how much UV energy is absorbed by the protective glass, I can't say for sure that equally powered T5's give off less heat than their metal halide counterparts, but it definitely seems like a possibility.
As I had mentioned previously, there is considerable variability in the efficacy of different halide lamps, and I wasn't sure whether that DOE data was using a lamp that would be equivalent to what we typically use. So I went to the websites of various bulb manufacturers and looked for spec sheets. Most didn't have any available, but Ushio and Iwasaki did. From what I was able to find on their sites, those bulbs range from about 42 to 72 lumens/watt. On the other hand, according to Current's website, their T5's deliver betwen 95 and 105 lumens/watt. As you pointed out, that energy that isn't being converted into visible light by the halides is either being converted into heat, IR (which for all practical purposes is the same as heat here) or UV (much of which will be converted into heat when it is absorbed by the glass layer between the bulb and the water). At the very least, within the context of our hobby and the equipment we use, it would appear that you can get the same amount of useful light out of a T5 with less energy consumption. Since I couldn't find any data on exactly how much IR and UV the bulbs we use put out, or how much UV energy is absorbed by the protective glass, I can't say for sure that equally powered T5's give off less heat than their metal halide counterparts, but it definitely seems like a possibility.
hurt
Active Member
Originally Posted by muggiwhplar
http:///forum/post/2651337
There's no need for the attitude there. I haven't attacked you personally; I'm just discussing data I've read regarding aquarium lighting systems, so let's calm down and not take ourselves too seriously. After reading your post, it seemed that we had each found at least somewhat reputable data to back up opposing claims.
Are you actually serious? I'm lost on this one.
Please show me where I wrote with an attitude? Please show me where I attacked you personally?
I thought this was quite the civil thread with reasoning to back up an argument.
http:///forum/post/2651337
There's no need for the attitude there. I haven't attacked you personally; I'm just discussing data I've read regarding aquarium lighting systems, so let's calm down and not take ourselves too seriously. After reading your post, it seemed that we had each found at least somewhat reputable data to back up opposing claims.
Are you actually serious? I'm lost on this one.
I thought this was quite the civil thread with reasoning to back up an argument.
muggiwhplar
Member
Originally Posted by Hurt
http:///forum/post/2651346
Are you actually serious? I'm lost on this one.
Please show me where I wrote with an attitude? Please show me where I attacked you personally?
I thought this was quite the civil thread with reasoning to back up an argument.
I thought you seemed to be taking on a condescending attitude, but these things are easy to misconstrue in text when there is no actual tone of voice or body language to accompany it. If you didn't mean any offense, then nevermind--my mistake.
http:///forum/post/2651346
Are you actually serious? I'm lost on this one.
I thought this was quite the civil thread with reasoning to back up an argument.
I thought you seemed to be taking on a condescending attitude, but these things are easy to misconstrue in text when there is no actual tone of voice or body language to accompany it. If you didn't mean any offense, then nevermind--my mistake.
hurt
Active Member
Originally Posted by muggiwhplar
http:///forum/post/2651390
I thought you seemed to be taking on a condescending attitude, but these things are easy to misconstrue in text when there is no actual tone of voice or body language to accompany it. If you didn't mean any offense, then nevermind--my mistake.
No problem.
http:///forum/post/2651390
I thought you seemed to be taking on a condescending attitude, but these things are easy to misconstrue in text when there is no actual tone of voice or body language to accompany it. If you didn't mean any offense, then nevermind--my mistake.
No problem.