Heat difference between wattage bulb question

THP · 08/12/2007, 01:53 PM

Am I right to say there is not much of a heat difference between running 5x250 DE MH vs 3x400 SE MH? I know this is a really stupid question but, I would think that the heat difference would be less with the 3x400....200 watts less or is there something else I'm missing here.

(P.S. Assuming electronic ballasts)

Nano Chris · 08/12/2007, 02:29 PM

I would assume with 3x400 watts you would get more heat than with 5x250 watts.

THP · 08/12/2007, 03:42 PM

I suspect the same as you however, I don't understand where the heat difference would come from when looking at it from a total wattage perspective.

bertoni · 08/12/2007, 05:11 PM

Well, the amount of heat produced would be measureable with a watt meter. The amount of light could be measured as well. If the ballast is removed from the tank, that heat doesn't much matter. All in all, I'm not sure much difference would be seen if the bulbs had similar output spectra.

THP · 08/12/2007, 06:20 PM

Thanks, I suspected as well that the difference in heat would be minimal. I'm interested in Luminarc reflectors and feel that the 19.5x19.5" reflectors produced the best output and distribution...better than the 13 or so inch DE mini reflector simply based on reflective surface. Seeing as I'd be going for that size reflector, might as well get the 400w.

08/12/2007, 01:53 PM	#1
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	Heat difference between wattage bulb question Am I right to say there is not much of a heat difference between running 5x250 DE MH vs 3x400 SE MH? I know this is a really stupid question but, I would think that the heat difference would be less with the 3x400....200 watts less or is there something else I'm missing here. (P.S. Assuming electronic ballasts) __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/12/2007, 02:29 PM	#2
Nano Chris Registered Member Join Date: Apr 2006 Location: Baltimore, MD Posts: 2,758	I would assume with 3x400 watts you would get more heat than with 5x250 watts. __________________ Chris ------- 34 Gallon Red Sea Max 130! Setup (Just got back into the hobby) Current Tank Info: 34 Gallon RedSeaMax!

08/12/2007, 03:42 PM	#3
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	I suspect the same as you however, I don't understand where the heat difference would come from when looking at it from a total wattage perspective. __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/12/2007, 05:11 PM	#4
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	Well, the amount of heat produced would be measureable with a watt meter. The amount of light could be measured as well. If the ballast is removed from the tank, that heat doesn't much matter. All in all, I'm not sure much difference would be seen if the bulbs had similar output spectra. __________________ Jonathan Bertoni

08/12/2007, 06:20 PM	#5
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	Thanks, I suspected as well that the difference in heat would be minimal. I'm interested in Luminarc reflectors and feel that the 19.5x19.5" reflectors produced the best output and distribution...better than the 13 or so inch DE mini reflector simply based on reflective surface. Seeing as I'd be going for that size reflector, might as well get the 400w. __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.