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StephenA
Sun, 31st Oct 2004, 11:59 AM
I just got a new Dual 250W MH fixture. How distance should it be from the water surface? I kept my old 150W 13" from the water.
::pete::
Sun, 31st Oct 2004, 12:12 PM
They say 8" - 10", but people keep them closer and obviously further.
JimD
Sun, 31st Oct 2004, 12:14 PM
The exact height is,,,, 7.27465297" above the surface. lol. Petes right on!
StephenA
Mon, 1st Nov 2004, 10:52 AM
I got it hung.
susannew
Mon, 1st Nov 2004, 02:22 PM
looks great! what is the company name on the dual 250 watt? we have been waiting for our 250w geisemann since march and lfs still does not have it in.. seems to be lingering in canada per lfs. have a loner from them but have not been able to put any corals or fish in ther cause we are still waiting for the light. Thanks;)
StephenA
Mon, 1st Nov 2004, 02:36 PM
It's a Geisemann. We've been waiting about the same amount of time.
susannew
Mon, 1st Nov 2004, 02:51 PM
thanks Stephan, will keep waiting then:) Wish they didnt take so long to get in, hope its worth the wait! No atinic on the loner but the snails and crabs dont care, lol.... They said another 2 weeks and I hope thats right this time.. been about to weeks every 2 weeks for a while, lol.. from what i've heard they are more energy efficient? i dont know much about lighting or equipment but is that true or is there really no difference? what kind of warranty did you get it with? thanks in advance:))
StephenA
Mon, 1st Nov 2004, 03:24 PM
It's got a 2 year warranty. They claim to be more efficient.
Tim Marvin
Mon, 1st Nov 2004, 05:30 PM
I run mine as close to the water as I can get them without getting spray on them. Mine sit about 5 inches, so that is the ideal distance.....LOL.. I'd say any place 12 inches or less. You are going to love the color change over the next few weeks!
GaryP
Mon, 1st Nov 2004, 08:19 PM
Must be a slow boat from Germany.

Gary
GaryP
Mon, 1st Nov 2004, 08:23 PM
Remember one thing. The intensity of light decreases with square of distance. So... what that means is that intensity (Par value) drops off quickly. Doubling the distance doesn't cut intensity by half, it cuts it by one fourth. And you only thought I was the chemistry guy. I know a little physics too.

I'm with Tim... get it as close to the water as you can without getting spray on the bulb or fixture.

Gary