Big heat difference between SE & DE (HQI)?

[azfishgal]

I just bought 2 IceCap 250W 14K MH Retro Kits (SE) with Lumenarc Mini reflectors for my 125 gallon tank (22" deep). I'm starting off with 2 to see how it looks and to try and keep down the heat and cost if I can. If I need to I can always add a third one with no problem. After I've placed my order I'm now hearing that SEs will run much hotter than DEs? Is this true? Should I have really gone with 150W? Did I make a mistake? I'm starting to second guess myself now.

This entire light issue is making me crazy!

 

[azfishgal]

See this is how crazy the light issue has made me....I put this in the wrong section. Can someone please move it to the Lighting section? Thanks!

 

[anonome]

azfishgal, this is a cut and paste from the web site....Wetwebmedia.com (Bob Fenners web site). Scott is saying that they run hotter, but with the proper ballast they should be cooler. I have done an aweful lot of research on this subject myself, switching from pc to hqi and couldn't be happier with mine. Check out this website for more info. Use the search key for more on the comparisons.
Double-Ended Metal Halide Bulbs?
Hi Bob and Gang,
<Scott F. your gang member tonight..>
I am going to upgrade my lights to metal halide from power compacts. I have noticed in some of the online retail stores that there is a double ended metal halide lamp that I haven't seen too much of. How effective are these compared to the more popular mogul based lamps? Do they run hotter? Do they use more or less electricity? Have you ever used these type of lights?
If you have how, in your opinion, did they perform?
And, more importantly are they less expensive?
Thank You for taking your time to answer my questions. John
<Well, John- let me start by telling you that I both use and recommend the double-ended halide bulbs. They are quite efficient, provide as much, if not more intensity and PAR than many mogul-type bulbs, and come in an ever-increasing range of wattages and spectra. The bulbs do run at a much higher temperature than moguls, but require electronic ballasts, of which there are many to choose from these days. Electronic ballasts tend to be a bit more efficient than the magnetic type ballasts. They do come in various wattages to suit many applications. Of equal, if not greater importance as the bulbs are the pendants that one employs with them. Many great models are out there for double-ended, by reputable manufacturers such as AquaMedic, PFO, and Sunlight Supply. I've seen a number of studies by serious hobbyists, such as Sanjay Joshi, which confirm outstanding results with double-ended bulbs when used in a well-designed reflector, and paired with a good ballast. Do a little research on various e-tailer's websites to see what models are available. There are a wide variety of prices, but on the whole, I'd venture to say that D/E bulbs and pendants are a bit more expensive than moguls, but worth the difference, IMO. Hope this helps! Regards, Scott F.>

 

[azfishgal]

Thanks Anonome. If I read this correctly then he is saying the DE run hotter than the SE, but with the right ballast it should run cooler. Is that right? I know he had some other points as well that I will have to consider. I already placed my order though, so if I'm going to change I have to try and catch the order before it leaves.

 

[anonome]

I would try to change it if possible. But on the other hand many people run mogul lighting with no ill effects as long as they have fans to cool the canopy. I would definately run many fans to try to cool them. If this was going to be a fixture over the tank with no canopy, I wouldn't be so concerned with the heat issue, but since it will have a canopy I would just compensate for the heat in other ways. Maybe you could leave part of the back open to help with the heat. Don't stress, I really think either way will be fine, just vent it somehow.

 

[azfishgal]

I will have a tall canopy with vents on the back and open top. I'll also have a fan blowing accross the top of the tank, it's the fan pictured below, but it's four fans, instead of two. So I'm hoping that will be enough. I added one of these fans to my sump and it's taken my temp down 2 degrees, so I'm sure it will help in the canopy as well. I guess if all else fells, I'll just have to break down and buy a chiller.

 

[autofreak44]

if you are overheating and you are about to go buy a chiller, try to blow a fan across your sump to, that could help. good luck with the tank azfishgal!

 

[azfishgal]

Originally Posted by autofreak44
if you are overheating and you are about to go buy a chiller, try to blow a fan across your sump to, that could help. good luck with the tank azfishgal!

Thanks, but if you read a little closer I said I did put one of those fans in my sump and it took it down 2 degrees.

We'll know if I'm going to need a chiller or not after my MHs are up. Thanks though for the tip, I do appreciate all the help I'm getting. My tank wouldn't be what it is without it.

 

[stanlalee]

the only reason I can see a DE running cooler than a SE is because of the sheild. Its already been proven take away the shielding, take away the reflectors, take away significant advantages in ballast performance a DE and SE bulb are virtually identicle in PAR and performance. Any difference in heat or anything else between the two are going to be shield,reflector and ballast related not the type of bulb.
as for WWM, I stop taking info at WWM at face value. you will find the different people responding conflict each other frequently and alot is just personal oppinion. 1rst of all DE bulbs dont have to have electronic ballast like they stated. 250w DE run on any ANSI code M80 magnetic ballast. 2nd not only do they run on magnetic ballast go to sanjays performance data site and compare any 250w DE bulb run by a magnetic PFO M80 ballast vs Ice cap or electronic ballast and you will find they typically perform signifcantly better on magnetic ballast.
Now I'm sure the extenral glass UV shield blocks, disperses, absorbs whatever it does to some amount of heat before it reaches the water unlike a SE bulb. how much I have no idea
a) I wouldn't lose any sleep over it and b) kill that bird when you get to it. As of now you are worrying about a problem that doesn't exist yet.

 

[azfishgal]

Originally Posted by Stanlalee
a) I wouldn't lose any sleep over it and b) kill that bird when you get to it. As of now you are worrying about a problem that doesn't exist yet.

Agreed.

I left my order the way it was and we'll just see what happens once I get everything up and running. I'm sure it will be fine, and regardless the lighting will be much better than what I have now.

Now we just need to get the canopy done so we can mount the lights.

 

[hurt]

HQI's run hotter from the test results I've seen. Google: cnidarian reef mh. On his test the PFO HQI ballast drove the temp reading up to 97.2 without any fans, an IceCap ballast drove the same Ushio bulb to only 85.2 under the same conditions.
As far as par is concerned, every test I've run on Sanjay's website shows SE produce more PAR when the UV sheild is used, and of course you have to use one with DE bulbs. Without the UV sheild DE produce a little bit more, but once you put the UV sheild on, they most always seem to produce less PAR than a SE bulb.

 

[stanlalee]

Originally Posted by Hurt
HQI's run hotter from the test results I've seen. Google: cnidarian reef mh. On his test the PFO HQI ballast drove the temp reading up to 97.2 without any fans, an IceCap ballast drove the same Ushio bulb to only 85.2 under the same conditions.
As far as par is concerned, every test I've run on Sanjay's website shows SE produce more PAR when the UV sheild is used, and of course you have to use one with DE bulbs. Without the UV sheild DE produce a little bit more, but once you put the UV sheild on, they most always seem to produce less PAR than a SE bulb.
The PFO is running hotter but also performing better. Can you have one without the other? (I'm sure some of it has to do with being less efficient as well though).
I have never run a SE test on the site with a sheild chosen. People do this in practice

I dont know how the sheild effects PAR but I would think that a piece of glass between the light and water would block or absorb some of the heat that would go to the water one way or the other.