MH reflectors

[renisel]

I currently have a Finnex 2X250W DE MH fixture on my 75 gallon reef tank. The reflectors are about as basic as they get, with five facets arranged in such a way that the reflector would have a trapezoidal shape if viewed from the front or sides (sorry if that's not the best description, but I don't know how else to describe it). Could anybody tell me, either through before-and-after pictures or some kind of quantitative comparison, what kind of boost in performance I could expect if I were to switch to something like a Lumenarc?

[renisel]

Bump...I'm sure somebody here either has or knows where I can find some info on approximately how much light I'm probably losing due to my very low-end reflectors.

[areze]

the difference I think is going to be about the dispersion of the light. the light is all going somewhere, and quite simply if its not escaping your hood, it is going down into the tank. the question is if its going down like a spot light or if its a broad even coverage of a defined area.

thats what a higher end reflector with more attention to angles will get you.

[renisel]

<a href=showthread.php?s=&postid=12759770#post12759770 target=_blank>Originally posted</a> by areze
the difference I think is going to be about the dispersion of the light. the light is all going somewhere, and quite simply if its not escaping your hood, it is going down into the tank. the question is if its going down like a spot light or if its a broad even coverage of a defined area.

thats what a higher end reflector with more attention to angles will get you.

I don't think that's entirely true. The farther the angle of incidence is from being perfectly perpendicular to the water's surface, the more it will tend to be reflected. The higher end reflectors tend to be deeper, allowing them to capture a decent amount of light that would otherwise be shot out at angles close to the horizontal, and redirect it in a more vertical direction. I would think this would cause a considerable increase in the amount of light that actually penetrates the surface.

[areze]

that could be the case also, but looks like you understand the goal, light shooting straight down evenly over a area of the tank. not focused, and not diffused out the side of the tank.