4" fan recommendation - Page 3

hahnmeister · #51 12/14/2007, 03:04 PM

Quote:

Originally posted by sjm817
A sales pitch for their fixture. Stacked bulbs? Hmm. Anyway, keeping the ends cool is not a new idea. I know my cooling setup is a compromise. I didn't want any visible fans or vents which is why I use the rear mounted fans. The temp is pretty cool in the hood, so it seems to work well enough. What would be a good way to measure the temp of the ends of the bulbs?

Right, not 'new' exactly, but something very few actually execute. I dont think your setup is a compromise really... if you just moved all your fans to the ends of the bulbs so the center isnt getting much airflow and the bulbs can warm up a little in the center, but the ends are getting blasted directly, I wonder if that wouldnt do it.

jamesdawson · #52 12/14/2007, 04:43 PM

Those Polar fixtures are certainly interesting.

It would seem however that their would be a fair amount of restrike between bulbs and for that reason and spread, a quality engineered flat-layout fixture with active cooling like the PowerModule is best for reefing applications.

sjm817,

You could get ahold of a laser pyrometer and do some thermal measurements on your bulb ends to see if they are at the optimum temp of 25 centigrade?

Is that what optimum is Jon?

James

hahnmeister · #53 12/15/2007, 01:43 AM

I think thats it... 25 is the goal for the cold spot, and 35 for the length of the bulb itself. Yes... makes the ATI and Fauna Marin solutions very appealing from the looks of it. The constellation has a system like the ATI, but I think the TX5 and Solar Flares operate like the Current USA/Coralife (from one end to the other).

sjm817 · #54 12/15/2007, 01:56 AM

That link you posted states 47C for the cold spot. 25C would be pretty difficult unless the lights were off.

hahnmeister · #55 12/15/2007, 06:24 AM

Oh, yes. So how about water cooled T5 bulbs?

jamesdawson · #56 12/16/2007, 01:24 PM

O.K., thanks sjm817--- 47centigrade is optimum.

Jon, I too have thought that using waterproof endcaps is most likely a hindrance vis a vis keeping the coldspot properly cooled. I have a 60" UltraSolaris that I'm going to try and switch out to the open twist and lock endcaps and put a shield on the fixture so it channels the air like on my PowerModul. Long term project though as I'm starting aquisition process for a big (500G) tank right now.

James

jman77 · #57 12/16/2007, 02:04 PM

"Oh, yes. So how about water cooled T5 bulbs?"

Cool idea, but I would rather have plain old fans at the ends ... one small fan at each endcap....

Have you seen the water cooled metal halides ? The attached design has a major flaw as it is directly cooling the bulb, which should be done as the bulbs require a certain temp to correctly operate. There is another water cooling design that has an outer and inner glass envelop , water runs between the the two glass envelope and the center does not have water, this is where the MH bulb goes.

hahnmeister · #58 12/16/2007, 04:43 PM

Yeah, but water cooling a halide makes no performance boost... halides dont suffer from heat... so I wonder what the application would be there.

As I am finding out, not all T5s have cold spots to cool either...

http://archive.reefcentral.com/forum...0#post11397260

So I wonder how to cool them....

jman77 · #59 12/16/2007, 05:44 PM

Water cooled halides are cool to the touch..

, so they don't heat up the tank : )

BradR · #60 12/16/2007, 07:07 PM

Water cooled halides sound great although I wonder how much PAR you'd lose. Gonna pull the trigger on the 250mm fans though. Thanks meister!

hahnmeister · #61 12/16/2007, 07:24 PM

Regular halides with a fan/ducting system dont either. Conducted heat isnt any consideration, and convective heat rises, so as long as you provide a means for the heat to escape, it shouldnt be a problem either. Otherwise, there is radiant heat, and well... that includes visible light, IR, and UV... so if you reduce one, you reduce the others really. I doubt water over the bulb is productive in that area. So a water cooled halide seems a huge waste to me.

Maybe if you needed to light plants during winter in a growing area, and then you could heat the water with the haldies as well. But thats about it. I doubt it would be worth the chore of having to clean off the jacket around the bulb when stuff gets in there. It seems useless...
http://www.sunbeam-online.co.uk/sbo/...d_lighting.htm

hahnmeister · #62 12/16/2007, 08:35 PM

Regular halides with a fan/ducting system dont either. Conducted heat isnt any consideration, and convective heat rises, so as long as you provide a means for the heat to escape, it shouldnt be a problem either. Otherwise, there is radiant heat, and well... that includes visible light, IR, and UV... so if you reduce one, you reduce the others really. I doubt water over the bulb is productive in that area. So a water cooled halide seems a huge waste to me.

Maybe if you needed to light plants during winter in a growing area, and then you could heat the water with the haldies as well. But thats about it. I doubt it would be worth the chore of having to clean off the jacket around the bulb when stuff gets in there. It seems useless...
http://www.sunbeam-online.co.uk/sbo/...d_lighting.htm