Halide Q & A

[Mike de Leon]

What is the difference between a 250 watt DE halide and 400 watt mogul. What is better..

[jblincoe]

from what i have seen, de are more efficient than mogul. however you kinda have to compare apples to apples, a 250 mogul to a 250 DE. Also one difference is the DE also need a uv glass sheild the moguls do not(it is built in). Other things to consider are electronic or magnetic ballasts, overdriving or not, reflectors, etc. Lighting is one of those things that is really hard to get a handle on for a lot of people including myself.

[jblincoe]

i guess i really didn't answer the question, so---the answer is it depends on what you like, what you are trying to accomplish, application etc.

[Mike de Leon]

Thanks for the effort in helping here, really appreciated!
I am just wondering if performance wise do I actually get better par with DE.

[jblincoe]

PAR is "photosynthetically available radiation", a lot goes into the Available part of that acronym. your par readings could be high closer to the bulb ie higher in the tank with a de, but the lower you go in the tank the par will fall off. 400 watt SE will probably place more PAR lower in the tank IMO i think it would have better penetration through the water collumn. on the other hand depending on the depth of the tank, it could be hard to acclimate corals to the 400 watts in a shallower tank.

[jblincoe]

oh yeah and again you would get different results if the se mogul was a 250watt in that case i would go with the DE setup as in my understanding they are a little more efficient in energy consumption than the standard magnetic SE balast and create a little more PAR

[Mike de Leon]

Thanks again. I wanted to go with the 400 watt SE just because there are a lot more bulb choices out there. I already have the 250 and I am looking to upgrade.
I have seen a lot of tanks with 400W set ups and most of them look wonderful.
I also want to go with pendants without any fluorescent supplements keeping the look clean.

[jblincoe]

i don't think you will be disappointed. as you said your options are definitely open with the se bulbs. also you should be able to place sps at various depths without too much trouble. as i said do be careful acclimating corals to the increased intensity. i occasionally have problems with bleaching on new peices and the only thing i can attribute it too is acclimation.

[kstallbe]

Can someone please recommend a good SE metal halide 175w bulb for use with a probe start (M57) ballast?

[Mike de Leon]

Originally posted by jblincoe
i don't think you will be disappointed. as you said your options are definitely open with the se bulbs. also you should be able to place sps at various depths without too much trouble. as i said do be careful acclimating corals to the increased intensity. i occasionally have problems with bleaching on new peices and the only thing i can attribute it too is acclimation.

THANKS!

[Madfronter]

I am throwing around the idea of upgrading my lighting for my 55 gallon tank. My current set up is a 4 x 55 watt PC set up. I was thinking about getting this set up:

• 1x 250W 15000K double ended MH bulb
• 2x 96W straight pins Actinic 460nm bulbs
• 8x Lunar LED bulbs.

Does anyone have this configuration? And if so what do you think about it after having it on the tank for some time?

[Mike de Leon]

What I just found out switching to 400 watt SE bulb is that it produces less heat than 250 DE. But the intensity is a lot more. Corals are happier. I have already noticed more growth and coloration in the two weeks i have had it. This is without any flourescent supplementation. Very simple set up. Just two 400 watt bulbs over a six foot long tank.
If you intend to keep SPS forget 250 watts. Go straight to 400 watts. You will not regret it. Double ended fixtures seem to cast more shadows due to design. SE reflectors are large and tend to have more coverage.
I had DE for a couple of years. They have hot spots and shadows.

Good luck!

[Zimster]

I've heard that if a beam of light is pointed out through the tank side, it will be contained by the glass. Is it reflected back in? or is it wasted? What effect does the black panel have?

the answer to that is both. Some is reflected and some is transmitted. The amount that gets reflected is dependent upon the angle at which the light interacts with the glass.

To have the beam of light fully reflected (total internal reflection {TIR}) the angle of light must be greater than the critical angle of glass from water. The indices of water and glass are 1.333 and 1.5 respectively. Using Snell's Law, the critical angle occurs at an angle of 62.7 degrees according to the normal (perpendicular to the glass). Any angle smaller will transmit light.

The black panel will just soak up all the transmitted light.

[cybrsufr]

Originally posted by Mike de Leon
Corals are happier. I have already noticed more growth and coloration in the two weeks i have had it.
If you intend to keep SPS forget 250 watts. Go straight to 400 watts. You will not regret it.
Good luck!

I could not agree more. I ran my 90G reef with 2x250DE 20K bulbsand the SPS grew and that is about all I can say. When I moved to my 180, I went with 3x400W Radiums and the Colors shifted very dramatically for the better, Growth EXPLODED literally (corals that grew 3" in a year while in the 90G, grew 3" in 3 months in the 180G). Granted there is more water volume, flow etc, but the lighting is so much better. Coverage is better with less shadows and dead spots. DE bulbs are a point light source and therefore produce a narrower beam of light when compared to a SE bulb.

[bimmerzs]

mike/cybrsufr...I have to disagree with needing 400 watters for sps. There is a lot more than light that determines coral growth/coloration. Blasting a coral with light doesn't necessarily make it grow more since various coral types only utilize a percentage of the light they receive...even deep water varieties only take in maybe 10-20% of received light, that's why placement of coral's based on light requirements is key. We all know 20K bulb's generally have half the par of lower kelvin bulb's, and the ballast also makes a big difference on the output/color of the bulb's. Cybrsufr, your comparison is not apples to apples, you had a bigger tank, more water volume, possible lower nutrient's and most likely greater stability, coupled with possibly doubling your light output. Not a real fair comparison. See here. http://www.athiel.com/lib2/lightclub.html

Cheers,

[tsiebel]

Originally posted by cybrsufr
I could not agree more. I ran my 90G reef with 2x250DE 20K bulbsand the SPS grew and that is about all I can say. When I moved to my 180, I went with 3x400W Radiums and the Colors shifted very dramatically for the better, Growth EXPLODED literally (corals that grew 3" in a year while in the 90G, grew 3" in 3 months in the 180G). Granted there is more water volume, flow etc, but the lighting is so much better. Coverage is better with less shadows and dead spots. DE bulbs are a point light source and therefore produce a narrower beam of light when compared to a SE bulb.

I have a question regarding your 180. I am in the middle of setting up a 180 and havnt decided on lighting yet. I love the look of MH's so I am going to go with those, However I really dont want to get a chiller at this point so I dont want the water to get to hot. How High above the water do you keep your 400's, I was thinking I would get 250's since the tank is only 24 deep.. Do the 400's really put off less heat?? I was also planing on supplimenting the 250's with t5's, are you doing this.

[jblincoe]

the 400s still put off some heat-quite a bit actually. I think what he meant was that the 250 DE fixtures get quite hot, DE fixtures are enclosed. they heat up inside the canopy. SE fixtures generally don't have glass so the heat escapes and is a little easier to exhaust using fans.

[savichus]

As for me I think SE Reeflux 10,000k combined with actinics supplement. light looks the best! Just my opinion!

[jblincoe]

just out of curiosity, what wattage is your SE fixture savichus? Also depth of tank?

[GREEKREEFER1]

i have a 144g half circle thats almost 30inch's deep. 4inch sb and my light hangs 8 to 9 inch above the water. i have a coralife pro with 2 250w MH and i keep them on for a seven hour period and my sps and lps love it.

[savichus]

I have 175w Reeflux 10k one at each side and 400w Reeflux 12k in the center. To be honest, I don't like the color of 12k Reeflux. But maybe it's just me. The depth of my tank is standard 24" with 4" sand bed covering 1" plenum. I don't have SPS at the bottom, but whatever I have is growing up pretty good! BTW I was looking at the pictures of different brand and color bulbs on some websites, but looks that it doesn't show how everything in tanks looks in real life! Or maybe it's just me...

[robojet]

I have a 24G Aquapod and i purchased a 150W Sunpod Fixture (double ended MH). The tank is 20" deep. I'm considering going with SPS only. I have no experience with MH, as I've always had T5. What would be the best bulb (including brand) for color and growth?

[Scubes]

Hi all! First post and it is a lighting question. I am setting up a 46 gallon tank (36"L x 20" H x 16" W) and considering picking up this Coralife Pro MH HQI Clamp-On DE 150W 14k used for a reasonable price. Would this sufficiently light up my tank? I am planning on keeping a couple of fish, live rock and a few softies. Would it be bright enough for LPS?

[jblincoe]

i would think so, you may want to go with a different kelvin rating on the bulb, but i would think it would do a pretty good job, just keep your light lovers as close to the middle of the tank as possible or directly below light. softies should do well in this setup.

[Scubes]

Thanks! I will make the deal for it.

i would think so, you may want to go with a different kelvin rating on the bulb, but i would think it would do a pretty good job, just keep your light lovers as close to the middle of the tank as possible or directly below light. softies should do well in this setup.