# METAL HALIDE vs T5 for 55g



## Dany (Oct 28, 2006)

I am having some trouble deciding which light fixture to use for my 55g tank (48”x 13”x20”). I am debating between a Tek T5 4’ 4 lamp fixture or 2 x150watt Metal Halide or 2x70watt Metal Halide. I’ve tried doing some research but I keep on getting different information. Could anyone please help with this decision. I would like to add that I would rather not spend too much on this light fixture but I am willing to spend the money when it means quality ( just not a extreem amount). Also, there might be a conversion into saltwater in the future and I do not want to buy another light fixture. 

All help is welcomed.


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## Dany (Oct 28, 2006)

Anyone?


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## Missy B (Jul 8, 2007)

If your thinking of upgrading to a saltwater, I'd go with the halides for sure. The metal halides have a higher PAR (photosynthetic active radiation) rating than the T5's. However, if you want to stick with the freshwater, I'd go with the T5's, due to the length of your tank.


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## Brilliant (Jun 25, 2006)

If you have money for metal halides then I would get a 75g...


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## ryzilla (Feb 3, 2007)

Go with the t5' HO for any application. Especially for a 55g which has a narrow foot print those halides would have to be lower or you will waste alot of light if you have them to high. T5's with parabolic reflectors are the most efficient way to light ANY aquarium and can grow ANY plant or coral as good if not better then halides. Halides are a thing of the past and new technology is always the best to have when efficiency and effectivness are in mind. You could get a 2x54w t5ho retro by SLS and grow low to high light plants. There are few plants that would require more light then that.


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## Dany (Oct 28, 2006)

I was looking into getting the tek t5 4' 4x54w but i am unsure if i should spend the money. Do you think the 2x54w t5ho retro would be enough to grow HC?


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## Chuppy (Aug 5, 2007)

I would say mH . though not needed but there is something about the shimmer that attracts me!

Drew


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## ryzilla (Feb 3, 2007)

Dany said:


> I was looking into getting the tek t5 4' 4x54w but i am unsure if i should spend the money. Do you think the 2x54w t5ho retro would be enough to grow HC?


In my 30g I had the 2x39w retro and I grew HC VERY easily. There is nothing that projects light more efficiently into a tank then a t5 HO with parabolic reflectors. In my experience you will be able to grow it with out worry. In my 5g planted nano I used to have a POS 24w aquatrader unit, it was total crap. I had HC planted but it was not looking how I wanted it. So I updraded to an AHsupply 2x13w bright kit. Now this was only a 2w upgrade, but the kicker was the parabolic reflectors that honestley put 1.5x more light into the aquarium. These also will not heat up your aquarium like halides or power compacts. They run much cooler and last twice as long Vs. Halides. I have been using the same 39w bulbs for about 18months now and I will probably replace them in two months or so. You also get more flexibility in T5's because the more bulbs you run the more you can mimic the sun rising and setting with multilpe on/off switches. If you really wanted to build your own unit with optimal lighting then you should get the workhorse 7 ballast and run a 3x54w and peice together all the other parts such as the endcaps, reflectors, and such. Dont let people talk you into halides because they mine as well talk you into getting POS VHO's with internal reflectors, BLAH, what a thing of the past. THis is my opinoin and I have been using T5's with parabolic reflectors for two years and it was the best advice I could have got. For starters I would go with the 2x54w but if you feel comfortable with the higher light challenge then 3x54w would be optimal but possible overkill. You wont be sorry with the 2x54w sun light supply, they are just fantastic units.


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## Dany (Oct 28, 2006)

ryzilla said:


> In my 30g I had the 2x39w retro and I grew HC VERY easily. There is nothing that projects light more efficiently into a tank then a t5 HO with parabolic reflectors. In my experience you will be able to grow it with out worry. In my 5g planted nano I used to have a POS 24w aquatrader unit, it was total crap. I had HC planted but it was not looking how I wanted it. So I updraded to an AHsupply 2x13w bright kit. Now this was only a 2w upgrade, but the kicker was the parabolic reflectors that honestley put 1.5x more light into the aquarium. These also will not heat up your aquarium like halides or power compacts. They run much cooler and last twice as long Vs. Halides. I have been using the same 39w bulbs for about 18months now and I will probably replace them in two months or so. You also get more flexibility in T5's because the more bulbs you run the more you can mimic the sun rising and setting with multilpe on/off switches. If you really wanted to build your own unit with optimal lighting then you should get the workhorse 7 ballast and run a 3x54w and peice together all the other parts such as the endcaps, reflectors, and such. Dont let people talk you into halides because they mine as well talk you into getting POS VHO's with internal reflectors, BLAH, what a thing of the past. THis is my opinoin and I have been using T5's with parabolic reflectors for two years and it was the best advice I could have got. For starters I would go with the 2x54w but if you feel comfortable with the higher light challenge then 3x54w would be optimal but possible overkill. You wont be sorry with the 2x54w sun light supply, they are just fantastic units.


Thanks for the info.

Are you saying that i can grow just about any plant with the 2x54w kit?


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## PAINKILLER1009 (Jan 3, 2007)

Dany said:


> Thanks for the info.
> 
> Are you saying that i can grow just about any plant with the 2x54w kit?


I have a TEK 4x54 on a 55g and can 4 sure grow what ever with a burst schedule. I would reccomend going with the 4 and not the 2 bulber. 
Just think you wouldn't have to upgrade if you got a bigger tank, and better lighting options.


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## ruki (Jul 4, 2006)

Chuppy said:


> I would say mH . though not needed but there is something about the shimmer that attracts me!
> 
> Drew


The aesthetics of metal halides are quite nice. You can't do that shimmer with T5 HO.


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## Dany (Oct 28, 2006)

ruki said:


> The aesthetics of metal halides are quite nice. You can't do that shimmer with T5 HO.


Ya I know what you mean. It is a site to see.

Well I officially bought the Tek T5 4' 4 bulb fixture with 4 Giesemann midday bulbs. I am very excited. I can't wait to get these.

I am wondering if I made a good choice or not for bulbs? I was thinking of mixing the bulbs but after some research, people on this form have had good luck with just running Giesemann midday bulbs... Does anyone disagree with this or did I make the right choice?


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## howie (Jan 5, 2007)

I use both and I prefer the versatility of the TEK T5. The ability to mix bulbs is really nice.

My advise for your new TEK. Suspend the fixture. It really heats up my tank, even suspended 9 inches.


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## BryceM (Nov 6, 2005)

I disagree that MH's are a thing of the past, but if you insist on using a 55g tank, T-5's would probably be a better choice. MH's do best when ligting a rectangular footprint. When it comes to effeciency it's hard to fault T-5's but they simply don't put out the same visual quality of light that you get with MH's.

The best advice on this thread was given by Brilliant. If you have the $$ for MH's then drop the 55g tank and get a different size: 50g, 75g, 90g are all good choices. The narrow depth of a 55 makes it a poor choice for aquascaping.


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## harsh (Jan 22, 2006)

Brilliant gave a small and point blank advice and people overlooked it, MHs are unmatched but they are best for deeper, wider tanks. I have a 3'x2'x2' custom made glass tank and i went with T5HOs it's penetration power is not sufficient for deep tanks and i always found them inadequate. I am moving to two 150W 6500K MHs soon and have no doubts whatsoever. 

But if you want to stick to your current tank T5s are the best option.


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## NoSvOrAx (Nov 11, 2006)

I agree with harsh. I have a 6x2x2 (180g) tank with 10x39w T5HO and it just doesn't have the punch to get to the bottom.


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## taekwondodo (Dec 14, 2005)

tagging along...

Been following this thread, and am putting together a 125G 72"x18"x18" tank - Debating over the HO T5s or 4 x 75W DIY MHs....

Love the shimmer of MH - will 4x75 spaced across the top be enough? Too much?

Thanks.


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## lino (Jun 11, 2007)

I'm just about to buy two 75W retrofit MH from catalina aquariums for my 65g (36 x 24 x 18) Is that enough juice or should I bump it up to 2 150W. I love the looks of MH's


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## hoppycalif (Apr 7, 2005)

I keep reading statements about "penetrating power" or "punch" being an attribute of certain types of light fixtures. Light just isn't that complicated. Given the same size bulb, same wattage, same lumens per watt, and the same reflector, any two lights will "penetrate" or "punch" the same distance in water. It is only the reflector, combined with a small physical size bulb, that determines how much light goes directly down thru the water. The smaller the bulb, either the diameter of a linear bulb, or the diameter of a spherical bulb, the more efficient the reflector will be at directing the light where it is pointed. That is the major reason T5 bulbs are more efficient than T8 bulbs. And, MH bulbs are the most efficient. Honest - that's all there is to it.


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## ruki (Jul 4, 2006)

hoppycalif said:


> It is only the reflector, combined with a small physical size bulb, that determines how much light goes directly down thru the water. ...


AND if the reflector sends light into the water at a 90 degree angle to the surface.



> And, MH bulbs are the most efficient.


Actually, LEDs are. They don't even need a reflector and some produce more than 150 lumens per watt.


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## BryceM (Nov 6, 2005)

Actually the sun is probably the most efficient......... and free too. 

All of this discussion back and forth about CF vs T-5 vs MH is a little frustrating to me. The instant a particle/wavelength of light comes out of a source it behaves exactly like any other. There is therefore no reason a MH fixture should "penetrate" better than any other.

This notion of "penetrating power" is probably a holdover from days when the only other options were NO or HO fluorescents. These did a fine job, but it was physically difficult to stack enough bulbs over a tank to get truly high intensities. People therefore had issues with lighting certain deep tanks. Any light source is capable of providing enough light near the surface. Look at how rotalas grow up near the top of the tank. "Back in the day" MH's were simply more powerful and did a better job over deep tanks.

Until someone with a light meter does some actual intensity tests under actual aquarium conditions, it's a bit meaningless to banter back and forth about which source is better. All three options work just fine. T-5's and CF's are pretty efficient. MH's are too. The single biggest difference to me is that MH lights act more like a point source, creating a nice ripple effect.

In a vacuum, light dissipates as distance from the source increases. Double the distance and the light intensity drops 75%. The refractory properties of the surface of the water, the water column, and the sides of the aquarium all mitigate this in real-world conditions, but light intensity still drops off as distance from the bulb increases. Deep tanks need more of whatever light source you decide to go with.


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## JamesC (Jul 26, 2005)

Where metal halides have the advantage is in the design of the reflector. They are much better at focusing the light in one direction so keeping the light brighter over a further distance. Fluorescents by their very nature, ie long, tend to scatter their light over a wider area and so the brightness of the light diminishes much quicker with distance. This is the reason why light from metal halides are able to reach the bottom of deep tanks better.



guaiac_boy said:


> In a vacuum, light dissipates as distance from the source increases. Double the distance and the light intensity drops 75%.


This isn't necessarily so. Focus the light in one direction and the brightness after one meter will be the same after one hundred meters. Think of how a laser works. Now a star for instance produces light in all directions and so yes with distance the brightness reduces.

James


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## BryceM (Nov 6, 2005)

I'm not aware of anyone currently using laser light to grow aquarium plants.

Good reflectors around any sort of bulb will get much of the light headed in the right direction, but to say that it doesn't dissipate with distance is simply incorrect. A reflector that casts a perfectly parallel beam would be a terrible choice for the aquarium. Only a small footprint, equal in size to the reflector, would be illuminated down at the substrate level.

Uggh. I guess I should probably fork over the money for a submersible light meter. I could demonstrate what happens in actual aquarium conditions between the surface of the tank and the substrate in deep aquariums. Is there anyone who hasn't noted beter color intensity and more rapid growth as plants grow toward the surface? Hasn't anyone else noted bare, ugly stems at the bottom of deep tanks, even when there is a ridiculous quantitiy of light going in at the top? Shading is one factor. Distance from the light source does have an effect too. Were it not so, you could mount your fancy T-5 or MH reflectors up at the ceiling - 5 or 6 feet above the tank without penalty. Try it sometime.


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## jazzlvr123 (Apr 29, 2007)

guaiac_boy I think reading through this post yours has been the most helpful to me thanks for being so smart : ) I have a light meter which i got from tom barr but The only thing i have to test it with is Metal halides because that is all I use on ALL of my tanks (either MH of HQI) I have 800 watts of MH going over a 180 gallon tank and I can virtually grow any high light plant i want. The tank is two feet tall and I still have enough light at the substrate to have my HC pearl like crazy


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## BryceM (Nov 6, 2005)

Thanks.

I have 450W of MH over my 180g tank for only 4.5 hrs/day and it grows HC just fine too. This is supplemented by about 1 wpg of T-5 lighting. Honestly, it's easy to over-do it with big tanks. About 2 or 2.5 wpg will grow about anything IME.


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## ruki (Jul 4, 2006)

JamesC said:


> This isn't necessarily so. Focus the light in one direction and the brightness after one meter will be the same after one hundred meters. Think of how a laser works. Now a star for instance produces light in all directions and so yes with distance the brightness reduces.


Not quite, in any aquarium, there are suspended particles in the water, so these absorb/block the light.

That's why sending light straight down into a tank results in more light at the bottom of a tank than light that has bounced around a few times off the front/sides of the tank. The longer path means more opportunity to get absorbed by a suspended particle.



guaiac_boy said:


> All of this discussion back and forth about CF vs T-5 vs MH is a little frustrating to me. The instant a particle/wavelength of light comes out of a source it behaves exactly like any other. There is therefore no reason a MH fixture should "penetrate" better than any other.


From basic geometry:
A long fluorescent tube with an excellent reflector sends light straight down into the tank off the reflector, but directly off the bulb, will not likely be straight down into the tank, so that will result in light scattering about providing less efficient "fill".

A PC bulb blocks more light from the reflector, shines light back into itself and generally has a non-excellent reflector, so that should result in less light reaching the bottom of the tank as compared to a linear bulb with an excellent reflector.

I too would love to see some actual measurements backing up what is predicted from the theory. It's all very straight forward, it's just a question of how much better it will be. I'm guessing there would be twice as many photons hitting the bottom from a TekLight or a Metal Halide as compared to a CF fixture.


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## BryceM (Nov 6, 2005)

There are many, many variables that come into play. Source voltage varies from outlet to outlet, ballasts vary - even between units from a single lot, bulbs aren't uniform, phosphor coatings vary tremendously, tank geometry isn't standard, reflectors shapes aren't standard, etc, etc. The behavior of light is poorly understood by most people, especially when you consider boundary conditions and refraction from air to water, water to glass, and air to glass.

Also, don't forget..... a CF bulb is nothing more than a regular T-5 bulb that is bent into a U shape. Otherwise they are identical. There tends to be more re-strike with CF units because of this, but it all depends on reflector design.


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## NoSvOrAx (Nov 11, 2006)

Ok first:
Light bulbs of all kinds dissipate the power they consume in 2 ways. Light and heat. The sum total of the light and heat they produce equals the power they draw. If a light produces more heat it is less efficient. MH bulbs produce tremendous amounts of heat. They are in no way, shape, or form more efficent than t5 or cf lights. It is not even a close comparision. But thats ok because having MH is not about efficiency, its about intensity.

Which brings us to the second:
Intensity is defined as power per unit of area. When people talk about watts per gallon or lumens per area they are actually talking about the measure of intensity. So lets compare t5ho and mh in regards to intensity. To make the math simple lets say my t5ho 6x39 fixture has a 3 square foot aperture. Lets also assume the that the t5ho bulbs are perfect radiators and produce only light with no waste heat. This means the max intensity for the fixture is 240 watts (rounding up) divided by 3 square feet which equaly 80 watts per square foot. No matter what you do, it is absolutely impossible to measure a higher intensity than this for this fixture unless you use an optical lens to focus the light to a smaller area, which is something no light fixture does, nor would you want one that did. Now lets take a 250 watt metal halide fixture with a double ended bulb in a reflector like those available from hellolights, and make the same assumptions. Lets says the reflector is approximately 12 inches by 6 inches, this isn't accurate but its good enough for this. This means that the MH fixture has 250 watts divided by .5 square feet or 500 watts per square foot. Thats over 6 times the intensity of the t5ho fixture. This is my definition of more punch or penetration. And if you don't think the MH fixture will absolutely destroy the t5ho fixture in comparision, I suggest you find physics book and convince yourself. Also it should be noted that the max solar intensity on this planet is around 1000 watts per square meter, which occurs along the equator. This is roughly 111 watts per square foot. So yes, at the distances we are talking about a MH is brighter than the sun.

Third:
As guaias boy pointed out cf = t5ho with a bend. Reflectors only salvage the light ejected off the wrong sides of the bulb. So when someone suggests that t5ho is going to put twice as much light downward into tank than cf, you can assume they haven't done the math. In fact, if you look at the cross-section of the bulbs & reflector and do the light ray diagram, which is about the only way to properly analyze this problem, you'll see that there is a difference but it is in fact not that large. This difference can almost be eliminated totaly by the simple addition of a ridge like bump running along the reflector directly above the seperation between the cf tubes. Which almost replicates the individual parabolic reflector chambers available on quality t5ho reflectors.


Finally, all this aside I would not recommend MH for a FW 55g but if your going SW I would go ahead and get a MH fixture. HTH

Also, I'd like to apologize if this had a crappy tone to it. I, like some others, am a bit fustrated. All three types of lights are great. MH allows you to have more light go into a deep tank, since you have a limited top area where you can put lights. T5HO and CF are cheap and efficient. It just bugs the crap out of me when people speak about these products from what sounds like some doctrine that is out of touch with reality.


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## tropism (Jul 21, 2006)

NoSvOrAx said:


> ... If a light produces more heat it is less efficient. MH bulbs produce tremendous amounts of heat. They are in no way, shape, or form more efficent than t5 or cf lights. It is not even a close comparision. But thats ok because having MH is not about efficiency, its about intensity.


I never could understand why people said that MH is more efficient than CF or T5HO. Even after taking into account that the heat from the fluorescents is spread over a larger area (and so might just 'seem' like it's less total heat), you find that there *is* actually less total heat and more light produced by T5HO than MH at the same wattage.



NoSvOrAx said:


> ... This means that the MH fixture has 250 watts divided by .5 square feet or 500 watts per square foot. Thats over 6 times the intensity of the t5ho fixture. This is my definition of more punch or penetration.


I'm sorry, I know this topic has been beaten to death already, but I couldn't help it.....:deadhorse:
I have to point out something that you missed in your analysis: the area that the light is going to be illuminating. As guaiac boy pointed out, nobody's using lasers as a light source for aquariums -- so it's not going to be the size of the light source or reflector that will tell you how many watts per square foot you're getting.

We're already assuming that these are perfect light producers (both 100% efficient). If we assume a 6x39 watt T5HO fixture is illuminating a 36"x18" aquarium, that's about 52 watts per square foot. Now, a 250 watt MH bulb is surely not going to be illuminating only a 12"x6" area (it's not a laser after all). It would be much more reasonable to assume that such a bulb would be covering at least an area 18"x24". That puts it at 83 watts (not 500) per square foot. Sure, you could potentially put more MH's to illuminate that area and you have a lesser ability to do that with T5s, but how many people need more than 250 watts on an 18"x24" area?

Now when we get to the "real" world, where we know that MH is less efficient than T5s, what happens? I did some searching and found this: Lumens per watt for MH: 50-56, average of what I found was about 52. Average lumens per watt for T5HO: about 80. So, using that and the stuff above we now have the T5HO producing 4160 lumens per square foot (52 watts/sq.ft. * 80 lumens/watt), and the MH producing 4316 lumens per square foot (83w/sq.ft. * 52 lumens/watt). Pretty close to the same amount of light per area, certainly not 6 times as much for MH as T5.

The only extra "penetrating power" you get from having MH is being *able* to put more light over the same area. But is more than 1 - 250 watt MH per 18"x24" area necessary on a plant tank?


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## NoSvOrAx (Nov 11, 2006)

tropism you are absolutely 100% correct. The intensities I calculated were at the fixtures themselves and represent power per unit of tank top space. And the ideal is not correct as t5ho and cf are both much more efficient than MH as your research shows. And as I was just pm'in hoppycalif, the real power of MH is the ability to put more watts on top of the tank because they take less space.

I feel kind of bad because we totally hijacked this thread from the original poster...


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## sayshrimp (Nov 5, 2007)

Wow! Alot of research has gone through and precalculated notations has been made. From what I can conclude is: Man, Ya'll can really get scientific with this lighting stuff. Cool beans! So tell me, What is the cost per wattage coverage? Which one is cheaper on the dollars and cents to run at the same volume of water?


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## BryceM (Nov 6, 2005)

Yeah, we did a pretty good job of hijacking here. Sorry to the OP. When I get a minute I'll pick this thread apart and move the irrelevant parts to an appropriate place in the "Science of Lighting" section.


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## ingg (Apr 8, 2007)

I'd appreciate seeing the hijack split off and continued.

I've seen a few statements here that confuse me, and some I'm not sure I agree with - but that said, I'm very new to higher end lighting, so would like to learn from the discussion!


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## ruki (Jul 4, 2006)

NoSvOrAx said:


> Third:
> As guaias boy pointed out cf = t5ho with a bend. Reflectors only salvage the light ejected off the wrong sides of the bulb. So when someone suggests that t5ho is going to put twice as much light downward into tank than cf, you can assume they haven't done the math. In fact, if you look at the cross-section of the bulbs & reflector and do the light ray diagram, which is about the only way to properly analyze this problem, you'll see that there is a difference but it is in fact not that large. This difference can almost be eliminated totaly by the simple addition of a ridge like bump running along the reflector directly above the seperation between the cf tubes. Which almost replicates the individual parabolic reflector chambers available on quality t5ho reflectors.


We can get specs as to what T5 HO, since it's pretty standard. I'm not all that certain as to what CF is, since there are so many flavors of them. Besides the connector variations, the bulb thickness isn't the same either. One of my CF bulbs is much wider than T5 and another one is much narrower.
Therefore, by the very definition of T5, CF can't always be T5 HO with a bend. It's not clear to me if all/any CF is at optimal brightness at 35C like T5/T5 HO or is at 25C like other fluorescent sources. Also confusing is that T5 HO tubes are supposed to last 2 years, but most CF aren't supposed to last a year.

Several questions on your reflector argument:
* Is there enough of a gap between the CF tube halves to insert a proper reflector? The CF tube halves I have seen are too close together to use the reflector that my TekLight uses. The reflector for side-by-side tubes requires a certain minimum space.








A much smaller reflector won't have space required for the bulb to represent a focus in a parabola.

* Are there any efficient CF reflectors out there utilizing a central divider and external wings? Is is practical to buy a TekLight or Ice Cap style reflector and cut it down to fit for a CF bulb? (The CF bulbs I've seen in aquarium fixtures are bent back without much distance between the tube halves.)

* Have you noticed that the TekLight reflector intercepts more than half of the light coming off the tube, since you can lay a ruler across the reflectors and not touch the tubes. When I look at the cross section ray diagram, it looks like twice as much light gets sent downward (nearly vertical) but the typical CF fixture out there with the rectangular polished box sends light out at many angles with much less light going out nearly vertical.



> Also, I'd like to apologize if this had a crappy tone to it. I, like some others, am a bit fustrated. All three types of lights are great. MH allows you to have more light go into a deep tank, since you have a limited top area where you can put lights. T5HO and CF are cheap and efficient. It just bugs the crap out of me when people speak about these products from what sounds like some doctrine that is out of touch with reality.


it bugs crap out of me, and likely some others, when people construct physically impossible devices to prove their point. 

Continuing to beat this dead horse... There are different lighting choices. All of them will work, but each has areas where it is most appropriate.

* T5 HO -- good compromise in efficiency and intensity when giving high light to a large area. Fixtures with high efficiency reflectors available.

* Metal Halide -- good for extreme intensity spot lighting. Also good for indoor ponds. When scaled up to larger pulse start bulbs, it's about as efficient as fluorescent in lumens per watt, but those are too large for most aquariums. The huge negative to Halides is lumen maintenance, bulbs get dim and change color much more rapidly than fluorescent.

* CF -- Optimal for compact spaces where linear tubes aren't long enough for good efficiency. Have not seen true high efficiency reflectors for these.

* T5 NO -- cheapest to operate in terms of lumens per watt, good for medium light tanks, but requires retrofit if you want a highly efficient reflector.

* T8 NO -- cheapest tubes and fixtures. High efficiency reflectors available as retrofits.

* T8 HO -- Poor man's HO using dirt cheap tubes and warranty destroying ballast manipulations


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## Newt (Apr 1, 2004)

Ruki and All,

The T refers to TUBE

a 5 means 5 eighths of an inch in tube diameter

a 6 means 6/8ths

an 8 means 8/8ths (or 1" diameter)

a 10 is 10/8ths

a 12 is 12/8ths or 1.5 inches in diameter.

Whether or not a CF is T5 it would depend on the diameter.

An F40/T10 means:

F = fluorescent
40 = wattage
and we have already covered T.

............and hey, there's the metric system....................still hasn't made it in the U.S.


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## Dany (Oct 28, 2006)

Don’t worry about it. There's no need to apologize. This is exactly what I wanted from the start. I wanted to compare the pros and cons of MH and T5HO. The post(s) made by members here were very helpful in the understanding of the MH and T5HO. Thank you to all who replied.

Incase anyone is wondering… I went with the Tek 4’ 4x 54w fixture with giesemann midday bulbs. The plants are doing great and the K temp on the bulbs make the tank look very natural. 

Dany


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## Newt (Apr 1, 2004)

Great choice.


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## Cliff Mayes (Jan 29, 2007)

Thank all of you who are participating! I suspected (before the response) that the OP was learning, just like me.

I think that I have learned more about lighting in the last few minutes than in the last year of digging and asking.

I have a couple of tanks (a 75 and a 20H) with GE bulbs in AH fixtures and they are very good.

I think that most of us just want something adequate that is economical as possible. C'mon LEDs!
Once the white light technology gets there and the price drops to reasonable I will be one of the first in line. I have been in this Hobby longer than most people have been alive and learning is the most important part.

A lot of you folk are very knowledgable about lights and all the explanations, like any info, breed a lot of questions that I will not ask so that I do not display my ignorance.

Thanks again and do not stop on our account.


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