quick par readings

[Doug]

Originally Posted by i have crabs

other things i tested was a 150w coralife(just the mh bulb) brand new 10k bulb was putting out 350 at the surface and only 100 about 10"down

Oh great. Guess I should have stuck with a 250w

[i have crabs]

the reef tank i tested with the pumps going normal, the cube i turned them down first, in the picture it looks like tons of surface movement but its mostly at the front

[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