quick par readings

[i have crabs]

ya wish i knew before, when ive seen par numbers on certin bulbs it's never said a size so i figure they would all be the same or at least close,before the tank even had water in it i knew it wasnt even gonna be close

[o.c.d.]

Does the surface agitation change any of the numbers? I noticed you have a lot of surface movement on the cube with the low numbers,and the other tank looks a lot calmer. I'd wonder how the physics of light refraction really matters. I've always tried to keep my surface agitation down for this reason. Hmm Myth?

[urbanhellfire]

Originally Posted by o.c.d.

Does the surface agitation change any of the numbers? I noticed you have a lot of surface movement on the cube with the low numbers,and the other tank looks a lot calmer. I'd wonder how the physics of light refraction really matters. I've always tried to keep my surface agitation down for this reason. Hmm Myth?

Good question, I have alot of surface agitation because I like the look of the light ( MH ) and the way it "ripples" in the tank. I wonder if it does effect par?

[o.c.d.]

Wavelets on the surface act like a lens and focus the light, causing glitter lines. These beams provide a strobe effect that increases the light intensity illuminating the bottom, briefly countering the attenuation of light with depth. They have been measured as having up to twice the intensity of light on the water surface. the effect requires a point source of light, such as the sun, metal halide, or halogen lamp. Reflected up off a white sandy bottom they also illuminate the undersides of reef ledges. J. Sprung The Reef Aquarium Vol 3
Sounds like halides get another point and so would sandy white bottoms, I do miss the glitter lines from my halides. I think I'm feeling buyer remorse

[Canadian]

I think it's been reported for years that longer T5 lamps produce greater PAR numbers and are more "efficient". At least I'm pretty sure Grim or Hahnmeister posted something to that effect on RC at least a couple years ago.

[i have crabs]

ya but thats on rc, now that its on canreef ill care