250W DE or 400W SE... Confused

gofor100

New member
Alright...

I have heard some seemingly conflicting info from numerous individuals about lighting...so I want to clear something up.

Specifically, I am wondering if it is true that 250-watt DE/HQI metal halide lamps put out as much or close to as much 400-watt SE metal halide lamps.

Now before you laugh, I know how silly this statement might sound since all I have ever read is that the best way you can judge the amount of usable light for invertebrates in the tank is the wattage of a lamp. So this would infer that a 400-watt ANYTHING (SE or DE/HQI) would produce more usable light for invertebrates.

And so you know what tank these lamps will be placed above... these will be used on my 300 gallon tank that is 36" tall which will house a mixed reef with mostly SPS, as well as clams at the bottom laying on a couple inches of sand. I want enough light so SPS could thrive throughout the tank and the clams would get a sufficient amount of light at the bottom of the tank.

FYI- I have tried doing a search on this topic, but for some reason the RC search feature is not currently working for me... so if you know of a good thread, you can also reference that as well.
 

nikon187

New member
It would all depend on bulbs ( Kelving rating), balasts, and reflectors..

For your tank I would run 400w just because of the 36" depth
 

gofor100

New member
See, that is what I was thinking... of course, if I can be more energy efficient with some DE 250W lamps, then I will.

I was thinking of using a mixture of 10,000K to 15,000K to get a blue-white look. I may also supplement with some actinic T-5's.

Anyone know of a good thread that already discussed this? I mean, I know that DE/HQI vs. SE can't be a new debate that I came up with... :)

Otherwise, feel free to provide your input.
 

nikon187

New member
I don"t think any 250 will support clams on the sand bed on a 36" deep tank. Especially when the halide will be off the water 8-10". I just don't think they will have enough par that far down, i may be wrong

I believe a 400 radium will give you the colour you want
 

RokleM

Premium Member
If you're going 36" tall, I think most would recommend 400w MH over 250. As a general rule, most seem to state that 250 up to 24" is a good recommendation. However you see people using a 150 on larger tanks and 400 on smaller.

As for par, yes it's very heavily dependent on ballast/bulb/reflector combo. With a lousy combo, you can get less light out of a 400 than a 250.
 

gofor100

New member
Good to know... I was leaning towards using 400-watt lamps even though it will be more expensive to run. The question then would be whether I should run 400-watt DE/HQI or 400-watt SE.

I have heard that the DE/HQI offer a more efficient and accurate spectrum of light (not sure what all of that means exactly), but obviously SE set-ups are generally more common and therefore, provide more 400-watt options.

Any input would definitely be appreciated.
 

JMaxwell

Most Interesting
It depends on what you mean by "400W SE". At one time, "SE" typically referred to lights that run on ANSI probe start ballasts and pulled about 400W out of the wall per bulb. This is no longer true as their are now SE bulbs designed to run on certain pulse start ballasts. The Radiums are an example of this.

Alsmost all bulbs that are "DE" are designed to run on pulse start ballasts and pull far more wattage than their designation. 250W DE often around 300W and 400W DE over 500W.

Also, newer bulb designs offer much greater PAR per watt than bulbs of just a few years ago.

I have a 40" tank. I run 250W DE Geismann 14.5K bulbs with Lumenbright reflectors. These reflectors are highly focused and the bulbs have quite high output per watt. I get good Acro growth as low as halfway down the tank. I wouldn't put a clam any lower than that.

If I had your setup, and wanted clams on the floor, I'd get Radium 400W with the appropriate ballasts and nice (Lumenbright/Lumenarc) reflectors. Good reflectors are highly important to getting the most out of your lights. Radium color and output are excellent.

I think the DE/SE debate has gone away as there are so many choices now. At one time, it was easier and cheaper to get SE bulbs and setups in the US and DE setups (with higher output and consumption at a given wattage designation) were largely from Europe and harder to get.

Good Luck!
 

gofor100

New member
JMaxwell... thank you very much for the info. It sounds like you've had to answer that question before :)

I'm definitely a rookie when it comes to metal halide lighting choice since I have mainly kept LPS and softies in the past.
 

gofor100

New member
So I was thinking of putting 3 to 4 MH lamps... being that the tank is 80"L X 24"W X 36"T, any suggestions as to the magic number of lamps (assuming I go with 400-watt lamps)?

I was also going to supplement the tank with T-5 actinics, but would that still be needed if I were to use the 400-watt Radiums? The look I'm going for is a white-blue look (I guess a little more white than blue), but a very crisp, clean look.

I'm not a huge fan of the deeper blue colors even though that usually brings out the flourescent colors of the corals... to me it looks a little too fake with that type of lighting.
 

RokleM

Premium Member
Most of the 400w bulbs are not that blue. As wattage increases, the blue decreases. For example, a 175w Hamilton 14k looks almost actinic like, and a 400w Hamilton 14k is crisp white.

A number of decent bulbs out there at 400w. Radium, Reeflux 12k, new Reeflux 20k, just to name a few. None really require supplementation, but it's not going to hurt either. I think your issue will be more of how deep can you successfully drive a T5? A lot of people mount them high up with their MH when supplementing, and I don't think that will work if you need 36".
 

gofor100

New member
So, maybe a good setup would be to do four 400-watt Radiums instead of three 400-watt Radiums supplementing with T-5's since the additional MH bulb would definitely provide additional usable light, whereas several actinic T-5's would probably not in a 36" deep tank... does that sound about right?

Thanks again for everyone's help... I'll need all I can get with lighting.
 

gofor100

New member
One issue I foresee with running only 20,000K bulbs though is the stunted growth rate my SPS may have since they would be under a higher Kelvin rating (my understanding is that they grow faster under lower Kelvin rating, i.e. 10,000K).

I guess I could set up a grow out tank for all of the frags I buy, put a 250watt 10,000K MH above those to let them get larger, then just place them into the display tank once they have reached a decent size. Any suggestions?
 

RokleM

Premium Member
Well, it depends on the reflectors, but yes you could put three or four MH over that setup. I personally would likely put three, since that's still ~26" of bulb coverage side to side.
 

gofor100

New member
Well only 3 bulbs (vs. 4 bulbs) would be good news for my electric bill! :)

FYI- I was thinking of going with JMaxwell's suggestion for reflectors (Lumenbright) in case that has any effect on future responses.
 

thecoralreefer

New member
Wattage is simplly a measure of used power
The lumins produced buy these bulbs and the color range
vary widely by manufactureres.
I would agree that a 400 would be better for the job at hand
they are right about power v depth to some degree but it is color that really penatrates to different depths. Some clams like the sand and some need more light than the sand bed offers.
Most corals in the sps will grow even at the 3 ft level w a 150.
but wattage and color make the zoxanthellea change color.
For instance an acropora sativa will have a brown ish color and when introduced to mh light it will turn purple.Add more light and the color deepens and is "heavier" And an acro cearealis will get green polyps to get the "tri-color" brn, grn, and purple.
Montipora " superman" will come in with brn polyps and purple skin. But add mh lighting the polyps start to turn purple. Go to 400 w and the polyps turn red. Bzzzzzzz
 

gofor100

New member
Much thanks CoralReefer... I'm definitely leaning towards the 400-watt SE bulbs.

I'm definitely looking to bring out the best colors of the SPS corals... would adding the fourth bulb really have a big effect on that?

Thanks again for any input...
 
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