Light distance ????

[crazy cajun]

Does it matter if your light is 6" from the water or 9"from the water?? my light would normally mount about 6" from water surface but with the canopy i have i need to sit it on top of the canopy rails that raise the light 3" that makes it 9" from the surface does this hinder the intensity of light???

 

[d2mini]

Height will change the par readings.
But depending on your water depth, corals you are trying to keep, and light intensity, those 3" might make no appreciable difference for you. Or it could mean having to make some coral placement adjustments if you are already borderline in light requirements.
But i would venture to guess you will be ok.

 

[reeffreak]

Yep air cuts down on PAR almost as much as water does.

Listen to Dennis.