T-5 lamps same output as Metal Halides!!!!!!!
- Thread starter usafresq1
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The T5 and m/h debate still draws on. My view is this
1 even if a t5 knocks out as much par as a m/h(which i'm sure it does not) You still dont and can not get the same affect with a flor lamp than you can with a halide.
2 All the hype is still happening and people still fall for it. If T5's were so good dont you think that all the experianced hobbyists with large sps tanks and the like, would use them? as i for one always strived for the best setup and was always dissapointed by T5's
3 People seem to think that T5's were designed exclusivly for the aqaurium trade this was not the case. They were actually designed for offices to give extra light and cheaper running. The ballasts are far better than the old style. But come on why fall for all the hype.
4 These t5 units were supposed to outlast a t8 and t12 tube as well? Now have you seen a T5 lasting a long time?
There will always be arguments against and for any product. The proof as far as i am concerned(for what it is worth) is seeing the 2 products working side by side, then you can make your own comparison. The running costs are not a factor with this little debate we are having, lets just stick to the facts that have been raised. LIGHT OUTPUT
1 even if a t5 knocks out as much par as a m/h(which i'm sure it does not) You still dont and can not get the same affect with a flor lamp than you can with a halide.
2 All the hype is still happening and people still fall for it. If T5's were so good dont you think that all the experianced hobbyists with large sps tanks and the like, would use them? as i for one always strived for the best setup and was always dissapointed by T5's
3 People seem to think that T5's were designed exclusivly for the aqaurium trade this was not the case. They were actually designed for offices to give extra light and cheaper running. The ballasts are far better than the old style. But come on why fall for all the hype.
4 These t5 units were supposed to outlast a t8 and t12 tube as well? Now have you seen a T5 lasting a long time?
There will always be arguments against and for any product. The proof as far as i am concerned(for what it is worth) is seeing the 2 products working side by side, then you can make your own comparison. The running costs are not a factor with this little debate we are having, lets just stick to the facts that have been raised. LIGHT OUTPUT
reefkeeper1":14po32zm said:
Yup, those ads usually fill up one session of bathroom reading. The best thing is some of the ads look like the same ones from 20 years ago. God, it's unbelievable how many problems people have with a simple sandbed when you read Goeman's Sandmail section
Time for a new Goeman's booklet, " Sandbeds For Dummies". :lol:
Something that may say something about the Author. I wrote an email awhile back requesting more info from her and where she purchased or received her products from etc.... Well I still haven't received a reply.
Perhaps I need to go back to my original plan of using PC's
I'd use MH but I have no real use for them right now.
Perhaps I need to go back to my original plan of using PC's
I'd use MH but I have no real use for them right now.
Good point.
People also fail to realize that there's little difference in VHO's, and especially T-5's vs PC's which are basically the same thing with one simply bent into a 'U'.
The only difference is the phosphors and elements used inside the tubes to emit specific spectra, and is this respect it seems that T-5 and VHO manufacturers have been more versatile and more progressive than the PC market. I mean seriously, with a PC you get a choice of what, 3 bulbs, and one of them always sucks? T-5's have better reflectors - yippy frikken do...The light from my 6500K MH can be seen reflecting through my window and off the neighboors house across the street making them pull their shades at night out of annoyance. How many T-5's will that take again?
Again, I've seen awesome tanks lit with tubes, and I might actually be convinced many large softies grow better under the wider, diffused light sources of a high intensity tube vs the collimated point light source of a MH. In the big picture though, you know were my vote lies.
For many of us who are limited by space or heating concerns, T5s or Power Compacts make the most sense. I am currently setting up a 10 gallon nano tank on my desk, and a couple 29 watt power compacts (overdriven to something approaching 45 watts each, haven't measured precisely yet) are the most sensible route to lighting the tank. It's hard to make an argument for a 70 watt metal halide bulb, with associated (hot or high priced, pick one) ballast, when I can light the tank quite well with a $70.00 lighting kit from ahsupply, and incur $26.00 per year in bulb replacement costs.
One day, when I have a large tank, metal halides will make the most sense. But until then, and for those of us with nano-tanks, T5s or PCs driven to intense levels fit the bill just right.
The author of the study is essentially driving two T5 F54W (4') bulbs on an IceCap 660 electronic ballast, and is pushing 80 watts rather than 54 watts through each bulb. The IceCap is quite capable of pumping out more than this. At the wattage levels given, you could accomplish the same thing for the cost of a Workhorse 7 ($35). The author is getting good reflection as well. Essentially, the author is putting 160 watts of light into a four foot tank using two bulbs that are 4' long and 5/8" thick. There is nothing that significantly advances the state of the art here--one could presumably slap a couple 55 watt 24" PC bulbs in there (end to end) and overdrive them to 80 watts each, and you'd see roughly the same level of intensity.
The importance of this study is the fact that it can be done, and over a long period of time can be used to keep corals healthy.
The advantage of this approach is that for $60 or so each year for bulb replacement costs, you can light a 4' tank. The disadvantage is that two 250 watt MH bulbs would light it better. Still, for a soft coral tank, you can't beat it! You certainly can't light it with one MH bulb, and NO or even HO T12 tubes will not penetrate the water as well. Cost wise, this approach probably makes a great deal of sense for those of us who don't want to put out the money for a couple metal halide ballasts and the associated $120-$180 per year in bulb replacement costs. You do get more light with the metal halide bulbs, but maybe that's a tradeoff you're willing to make.
It's an interesting study that would be fun to replicate. For anything over two bulbs on a four foot tank, though (160 watts), I don't see that it makes sense--replacing two metal halide bulbs (which would light the full four foot tank) would be more cost effective as soon as you got over two T5 bulbs. But for a smaller tank or lower light tank, this is a useful study.
Later!
Raph
One day, when I have a large tank, metal halides will make the most sense. But until then, and for those of us with nano-tanks, T5s or PCs driven to intense levels fit the bill just right.
The author of the study is essentially driving two T5 F54W (4') bulbs on an IceCap 660 electronic ballast, and is pushing 80 watts rather than 54 watts through each bulb. The IceCap is quite capable of pumping out more than this. At the wattage levels given, you could accomplish the same thing for the cost of a Workhorse 7 ($35). The author is getting good reflection as well. Essentially, the author is putting 160 watts of light into a four foot tank using two bulbs that are 4' long and 5/8" thick. There is nothing that significantly advances the state of the art here--one could presumably slap a couple 55 watt 24" PC bulbs in there (end to end) and overdrive them to 80 watts each, and you'd see roughly the same level of intensity.
The importance of this study is the fact that it can be done, and over a long period of time can be used to keep corals healthy.
The advantage of this approach is that for $60 or so each year for bulb replacement costs, you can light a 4' tank. The disadvantage is that two 250 watt MH bulbs would light it better. Still, for a soft coral tank, you can't beat it! You certainly can't light it with one MH bulb, and NO or even HO T12 tubes will not penetrate the water as well. Cost wise, this approach probably makes a great deal of sense for those of us who don't want to put out the money for a couple metal halide ballasts and the associated $120-$180 per year in bulb replacement costs. You do get more light with the metal halide bulbs, but maybe that's a tradeoff you're willing to make.
It's an interesting study that would be fun to replicate. For anything over two bulbs on a four foot tank, though (160 watts), I don't see that it makes sense--replacing two metal halide bulbs (which would light the full four foot tank) would be more cost effective as soon as you got over two T5 bulbs. But for a smaller tank or lower light tank, this is a useful study.
Later!
Raph
I dunno, I kinda like my 70 watt halide over my nano. My ballast barely gets luke warm, the bulbs are a little high, but I prefer the water penetration I get from it with the PFO reflector. I don't know if they even have t-5's small enough for my tank. Temps have never been a problem for that matter either.
Actually, from a cost perspective, I don't think T5's make as much sense for small tanks as they do for larger (longer) ones. Here's why, T5 bulb cost doesn't change very much with length. The 24W sunlight bulbs are ~$24 and the 80W ones are only ~$28. Just as a comparison for a 2' tank using an equivalent amount of Wattage would run $96 for 96W of T5, whereas you could probably get a 100W MH bulb for quite a bit less, say around $75. If you needed more light it would get even worse.
Now for a 6' tank things get a little different. If I compare 3x250 MH's at ~$270 with 8x80W T5 (which an IC 660 will actually drive at ~100W each, for a total wattage comparable to 3x250 MH's on an electronic ballast) at ~$224, the T5's start to have an edge.
One very important factor is being overlooked here though, that's bulb life. I think most people change their MH's at between 12 and 18 months. While data is admittedly still very sparse, T5 manufacturers have done bulb tests demonstrating that the GE 6500K bulbs lose less than 20% of their intensity after 5 years of use. Most of what I've seen for aquarium use recommend changing T5's at between 2 and 3 years. On average that's twice the bulb life of MH's.
Also, fluorescent bulbs become more efficient with length as well. And to begin with, fluorescent bulbs are more efficient at turning energy into light than MH bulbs are. They generate more lumens per Watt. In fact, fluorescents are currently the most efficient bulbs commonly available. Also, T5 bulbs are more efficient than the older T12's and PC's as well. The big problem with PC's and T12's though, is that an effective reflector cannot be made for them due to their width. A reflector with the same efficency as the SLS and SLR T5 reflectors would need to be ~8" wide to work with a T12 bulb. If you don't think reflectors are important, just go take a look at Sanjay Joshi's MH reflector tests.
T5 fluoresecents are used extensively in industrial lighting applications where efficiency is critical and intensive cost analyses are done. T5's have also been used to light many spectacular reefs in Europe for several years now. I have no doubt that healthy, vibrant reef tanks can be maintained under either T5's or MH's (and even VHO's and PC's). What's the most efficient way to light a reef tank? Only time will tell, but it certainly looks like T5's will be a serious contender.
I've been told that a manufacturer of T5 reflectors has sent a complete setup to Sanjay Joshi for testing. I'm sure the results of those tests will provide some answers to these questions.
Now for a 6' tank things get a little different. If I compare 3x250 MH's at ~$270 with 8x80W T5 (which an IC 660 will actually drive at ~100W each, for a total wattage comparable to 3x250 MH's on an electronic ballast) at ~$224, the T5's start to have an edge.
One very important factor is being overlooked here though, that's bulb life. I think most people change their MH's at between 12 and 18 months. While data is admittedly still very sparse, T5 manufacturers have done bulb tests demonstrating that the GE 6500K bulbs lose less than 20% of their intensity after 5 years of use. Most of what I've seen for aquarium use recommend changing T5's at between 2 and 3 years. On average that's twice the bulb life of MH's.
Also, fluorescent bulbs become more efficient with length as well. And to begin with, fluorescent bulbs are more efficient at turning energy into light than MH bulbs are. They generate more lumens per Watt. In fact, fluorescents are currently the most efficient bulbs commonly available. Also, T5 bulbs are more efficient than the older T12's and PC's as well. The big problem with PC's and T12's though, is that an effective reflector cannot be made for them due to their width. A reflector with the same efficency as the SLS and SLR T5 reflectors would need to be ~8" wide to work with a T12 bulb. If you don't think reflectors are important, just go take a look at Sanjay Joshi's MH reflector tests.
T5 fluoresecents are used extensively in industrial lighting applications where efficiency is critical and intensive cost analyses are done. T5's have also been used to light many spectacular reefs in Europe for several years now. I have no doubt that healthy, vibrant reef tanks can be maintained under either T5's or MH's (and even VHO's and PC's). What's the most efficient way to light a reef tank? Only time will tell, but it certainly looks like T5's will be a serious contender.
I've been told that a manufacturer of T5 reflectors has sent a complete setup to Sanjay Joshi for testing. I'm sure the results of those tests will provide some answers to these questions.
I think T-5s are a great lighting alternative and the best of the fluorescent options IMO, but comparing them to metal halides is really comparing apples to oranges. They function in different ways and each has properties that make it more or less suited to certain applications. I guess it depends on your goals...
Halides act like a point source and IMO penetrate/focus far better than any fluorescent (diffused) light. This is a great asset in deeper aquariums and also in tanks where you're looking for maximum irradiance levels down onto your animals (ie. SPS/Clam/Anemone tanks).
As for the lamp life claims - the 5 year thing is actually nothing unusual. Most commerical lamps, both fluorescent and halide are rated for 20,000 hours these days (over 5 years at 10 hours of use per day). Actually, many of the better commerical halide and high pressure sodiums (HPS) lamps are rated for 24,000 or even 30,000 hours (ie. more than T-5 fluorescent lamps).
That doesn't translate to aquarium products real well though. Lamps in our hobby with their specialized (bluer) spectrum tend to degrade much quicker than regular commercial lamps. Also, most reefers don't want to shock their critters when they change-out lamps so generally we're pretty conservative about using our lamps for less than their rated life.
As for how well T-5 aquarium lamps will last - IMO the jury is still out. Remember the claims of PC lamp life when they first started getting popular in the hobby? No matter what the manufacturers claim, the fact remains that they are still fluorescent lamps - not some miracle technology. Time will tell...
As to the efficiency thing - I agree that in general, T-5 lamps are more efficient at turning electricity into light than say T-12s, T-8s and PCs and also allow for a more efficient reflector design. I disagree, however, that they are the most efficient form of commonly available lighting. Using commercial lighting applications as an example (where plenty of comparison data is available), there are many MH and HPS lamps that are equally or more efficient than T-5 lamps when it comes to lumens-per-watt generated.
That said, IMO that criteria alone is not very solid ground to base an argument on about which of the two is the more efficient reef lighting setup. IMO the most important criteria would be how much light is actually getting to the corals vs. how much power is being consumed. Needless to say there are quite a few variables in that comparison, and in my mind, the only way to make a meaningful evaluation would be with a watt meter and a PAR meter, taking readings at different depths where corals would be present in the tank.
Just a few thoughts to add to the discussion...
Halides act like a point source and IMO penetrate/focus far better than any fluorescent (diffused) light. This is a great asset in deeper aquariums and also in tanks where you're looking for maximum irradiance levels down onto your animals (ie. SPS/Clam/Anemone tanks).
As for the lamp life claims - the 5 year thing is actually nothing unusual. Most commerical lamps, both fluorescent and halide are rated for 20,000 hours these days (over 5 years at 10 hours of use per day). Actually, many of the better commerical halide and high pressure sodiums (HPS) lamps are rated for 24,000 or even 30,000 hours (ie. more than T-5 fluorescent lamps).
That doesn't translate to aquarium products real well though. Lamps in our hobby with their specialized (bluer) spectrum tend to degrade much quicker than regular commercial lamps. Also, most reefers don't want to shock their critters when they change-out lamps so generally we're pretty conservative about using our lamps for less than their rated life.
As for how well T-5 aquarium lamps will last - IMO the jury is still out. Remember the claims of PC lamp life when they first started getting popular in the hobby? No matter what the manufacturers claim, the fact remains that they are still fluorescent lamps - not some miracle technology. Time will tell...
As to the efficiency thing - I agree that in general, T-5 lamps are more efficient at turning electricity into light than say T-12s, T-8s and PCs and also allow for a more efficient reflector design. I disagree, however, that they are the most efficient form of commonly available lighting. Using commercial lighting applications as an example (where plenty of comparison data is available), there are many MH and HPS lamps that are equally or more efficient than T-5 lamps when it comes to lumens-per-watt generated.
That said, IMO that criteria alone is not very solid ground to base an argument on about which of the two is the more efficient reef lighting setup. IMO the most important criteria would be how much light is actually getting to the corals vs. how much power is being consumed. Needless to say there are quite a few variables in that comparison, and in my mind, the only way to make a meaningful evaluation would be with a watt meter and a PAR meter, taking readings at different depths where corals would be present in the tank.
Just a few thoughts to add to the discussion...
blastermqn":2aa44cv4 said:
Think that could depend on what's in the tank....
I've got a 10gal that's a jelly tank (Cassiopeia sp.) and from all I've found on them, they'll do best under MH....I'm currently looking into a nice pendant once we get moved into our new house...probably redesign the tank at the time too....
Unfortunately, as is usually the case with lighting there is very little actual mfg data to rely upon. Where data does exist, it is usually not consistent with each other making it very difficult to do comparisons. The only real data we have to work with is that created by Sanjay and others like him.
In regards to bulb life, I have been told that MH bulb life tests are done to bulb failure as opposed to a loss of lumens which is the type of data I've seen for T5's (and these are the same GE 6500K bulbs being sold to aquarists, in this case). My understanding is that MH bulb tests are done to a point where 50% will no longer fire. Not a very useful test IMO. While MH aquarium bulb life is generally accepted form years of experience, we still know very little about T5's other than the 6500K bulbs. I do know they run relatively cool which seems to have a direct impact on the life of fluorescent bulbs in general.
The comments on efficiency are from a conversation with Sanjay at a presentation he gave for our local reef club. I have also seen reference to this elsewhere. This is purely theoretical efficiency and there are very small differences between the bulb types. Obviously, other factors such as bulb color matter far more than type when it comes to overall efficiency. But, watt for watt, a well made 6500K T5 should be able to generate more light than a similar colored MH bulb. Granted not much more, but certainly not less. HPS bulbs are very close to fluorescents in efficiency, but I don't think they have much applicability in the aquarium hobby (I do have one over my mangrove refugium, though).
And it is definitely light in the tank that matters. This is why the efficiency of the T5 reflector is so important.
T5's and MH's definitely both have their strengths and applications. I'd guess that we'll start seeing more T5's and fewer PC's and T12 VHO's, and that T5's will make a dent in the MH market as well.
In regards to bulb life, I have been told that MH bulb life tests are done to bulb failure as opposed to a loss of lumens which is the type of data I've seen for T5's (and these are the same GE 6500K bulbs being sold to aquarists, in this case). My understanding is that MH bulb tests are done to a point where 50% will no longer fire. Not a very useful test IMO. While MH aquarium bulb life is generally accepted form years of experience, we still know very little about T5's other than the 6500K bulbs. I do know they run relatively cool which seems to have a direct impact on the life of fluorescent bulbs in general.
The comments on efficiency are from a conversation with Sanjay at a presentation he gave for our local reef club. I have also seen reference to this elsewhere. This is purely theoretical efficiency and there are very small differences between the bulb types. Obviously, other factors such as bulb color matter far more than type when it comes to overall efficiency. But, watt for watt, a well made 6500K T5 should be able to generate more light than a similar colored MH bulb. Granted not much more, but certainly not less. HPS bulbs are very close to fluorescents in efficiency, but I don't think they have much applicability in the aquarium hobby (I do have one over my mangrove refugium, though).
And it is definitely light in the tank that matters. This is why the efficiency of the T5 reflector is so important.
T5's and MH's definitely both have their strengths and applications. I'd guess that we'll start seeing more T5's and fewer PC's and T12 VHO's, and that T5's will make a dent in the MH market as well.
FWIW, I agree with most of what you're saying, but I'm just not convinced on a few points, such as...
or this one...
I work with commercial lighting and checked on specs for some of the better MH and HPS lamps to compare against the best T-5 I could find, just out of curiosity. Granted this is commercial stuff and I have no idea how this correlates to our bluer spectrum reef lamps...
Type|Wattage|Color|Int. Lumens|Avg Lumens|Int. Lumens/Watt|Avg Lumens/Watt|Life (Hrs)
T-5|54|4100K|5,000|4,700|93|87|20,000
MH|400|4200K|44,000|35,200|110|88|30,000
HPS|360|2100K|45,000|40,500|125|113|24,000
Keep in mind, as you go to the really high wattage MH and HPS (ie. 1000 watts and up) they get significantly more efficient than this, but for the purpose of this discussion I stuck with lamps that fall in the more common wattage range used in the hobby.
I checked-on T-5s and MHs that were warmer colors too, like 3000K, 3500K, 4000K - no real difference in #s though. BTW, according to the rating numbers, T-5s were more efficient than T-12s, T-8s, and PCs for any comparable model lamp listed.
All that said, even if we concede that T-5s are equal or slightly better than MH in watts used/light generated efficiency (with regard to aquarium lamps) there's still the problem of geometry. You just can't pack the same amount of wattage in the same area with T-5s as you can with MHs. You can never generate the same sort of intensities you can generate with MHs.
PRC":vbjx9riv said:
or this one...
PRC":vbjx9riv said:
I work with commercial lighting and checked on specs for some of the better MH and HPS lamps to compare against the best T-5 I could find, just out of curiosity. Granted this is commercial stuff and I have no idea how this correlates to our bluer spectrum reef lamps...
Type|Wattage|Color|Int. Lumens|Avg Lumens|Int. Lumens/Watt|Avg Lumens/Watt|Life (Hrs)
T-5|54|4100K|5,000|4,700|93|87|20,000
MH|400|4200K|44,000|35,200|110|88|30,000
HPS|360|2100K|45,000|40,500|125|113|24,000
Keep in mind, as you go to the really high wattage MH and HPS (ie. 1000 watts and up) they get significantly more efficient than this, but for the purpose of this discussion I stuck with lamps that fall in the more common wattage range used in the hobby.
I checked-on T-5s and MHs that were warmer colors too, like 3000K, 3500K, 4000K - no real difference in #s though. BTW, according to the rating numbers, T-5s were more efficient than T-12s, T-8s, and PCs for any comparable model lamp listed.
All that said, even if we concede that T-5s are equal or slightly better than MH in watts used/light generated efficiency (with regard to aquarium lamps) there's still the problem of geometry. You just can't pack the same amount of wattage in the same area with T-5s as you can with MHs. You can never generate the same sort of intensities you can generate with MHs.
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