egg crate reduce or increase the amount of light in your tank

[Snarkys]

does it block light or reflect more light in ?

[Snarkys]

opps

[AnemicOak]

Good question. I was wondering the same thing. The LFS guy say it'll block a ton of light, says open top is the only way to go. I'd like to use this stuff for a couple different reasons.

Has there been any actual tests by anyone? Maybe something in Advanced Aquarist? I looked, but didn't see anything.

[dgin]

Eggcrate blocks some of the light. Thats why some lighting fixtures have them - to help diffuse the lighting.

[Snarkys]

i put it on last night and the tank looks even brighter than before, thats why i ask. if it does block any it cant be much . in my case it seems to be reflecting more light back into the tank .

[reefmarker]

It matters. When I put eggcrate on 2 of my tanks I also put the lights down right on top of the eggcrate. The lights were up about 6" off the water to start with.

I don't think the eggcrate blocks very much light. It has to block some light. It is opaque.

[Snarkys]

you dont think it can help refelect light that bounces of the top of the water back into the tank ?

[polcat_4u]

If you look close at the construction of most eggcrate there is a right and wrong way to install it. It is tapered ever so slightly towards one side and this helps refocus the light into the tank, that in turn offsets the opaque portion of the grid. Next question, which way is correct? The tapered (or finished) edge goes towards the water.

[Snarkys]

ours is not tapered.

[Snarkys]

LOL NM , i guess it is . i have two peices cut ..... one is rhe right way and one is the wrong way . now you want the narrow part closest to the water and the thick part closest to the light, i take it ?

[Pez Vela]

The aluminized (in color, still plastic) egg crates are designed to reflect and refract light downward. That is why you see them on all of the 2x4 fluorescent lighting fixtures in office buildings. More light for a lower wattage fixture. Now in the case of high wattage MH's or similar, I guess I will just have to try it out..... Can't cost too much to give it a try.

Mike

[Steven Pro]

Originally posted by Snarkys
LOL NM , i guess it is . i have two peices cut ..... one is rhe right way and one is the wrong way . now you want the narrow part closest to the water and the thick part closest to the light, i take it ?

No, you want the narrow part towards the light. So that it looks like this when viewed from a cut away side,

|\ /\ /\ /\ /\ /\ /\|

This way it grabs the available light and focuses it downward. Dana Riddle talked about this at a MACNA several years ago. I believe it was the second Louisville conference.

[Snarkys]

Originally posted by Pez Vela
The aluminized (in color, still plastic) egg crates are designed to reflect and refract light downward. That is why you see them on all of the 2x4 fluorescent lighting fixtures in office buildings. More light for a lower wattage fixture. Now in the case of high wattage MH's or similar, I guess I will just have to try it out..... Can't cost too much to give it a try.

Mike

i was told not to use the alumunized ones because over time it flakes off. i think the white reflects almost as much anyways.

[Snarkys]

Originally posted by StevenPro
No, you want the narrow part towards the light. So that it looks like this when viewed from a cut away side,

|\ /\ /\ /\ /\ /\ /\|

This way it grabs the available light and focuses it downward. Dana Riddle talked about this at a MACNA several years ago. I believe it was the second Louisville conference.

hmmmm

[Steven Pro]

Was my little character drawing good enough so you could envision it?

[Snarkys]

Originally posted by StevenPro
Was my little character drawing good enough so you could envision it?

ya .

i guess i thought haveing the angles pointing up like that would tend to reflect light up rather than down but having the thick flat side down would tend to refelct the light off the water back into the tank , rather than back up . well either way is is very little light lost i think . not enough to notice with the nakid eye . fek we thought it looked brighter.

[greenbean36191]

No, you want the narrow part towards the light. So that it looks like this when viewed from a cut away side,

I fail to see how that will reflect light into the tank. That is like yelling into the wide end of a megaphone and expecting the sound to be amplified on the other end.

[Entropy]

Actually that is only because the drawing is exaggerated. There is very little difference between the two sides (which is why a lot of people don't even notice it). I was on the eggcrate bandwagon for a long time and what I concluded finally is that it works very well at keeping critter in if you have jumpers, but it looks like crap with metal halides unless you like a nice grid pattern on the back of your tank. With VHO it is not as bad since the light is spread out and not point source. Bottom line is it is a excellent alternative to glass tops but not as good as completely open IMO.

[xrunner1234]

Here's another interesting question.

Does the eggcrate focus the light more straight downward so as not to hit the front glass and promote agae growth? Maybe stack mutiple ones on top of each other to 'focus' the light to only shine downward.

Can someone try this on 1/2 their tank and compare algae growth?

[tygger]

Interesting, I didnt notice that it was tappered.

[Snarkys]

found this somewhere

This is a Silver Wide Flood Intensifier egg crate for the Arri Studio Cool 4 fluorescent fixture. In addition to slightly narrowing the beam spread to about 60°, it intensifies -- boosts the light level, and "hardens" the quality of the light to give more dramatic shadows.

Egg crates are essential accessories for any lighting system. An egg crate alters the shape and intensity of the light output from your light fixture. Consider an egg crate as a painter would a brush, or a sculptor would a knife, or chisel.

An egg crate is a rigid, or semi-rigid plastic or metal grid that narrows the spread of light. The spread of light will be determined by the density of the honeycomb mesh, and the distance of the subject from the light. Unless specified otherwise, an egg crate mounted on a light fixture will limit the spread of light to 40° from the face of the fixture.

[Chris Lakies]

Its funny you should mention this because I'm currently aclimating from 20k to 10k.

I started off with just the egg crate over the top of my tank. I have one metal halide in the very center (250 watt pendant). The light is a tad bit blocked directly underneth the pendant but every where else it is severely blocked because the egg crate is about 1/2" wide so it is cutting down the horrizontal spread of the light.

NOTE: It would also depend on the hight of the pendant from the egg crate.

Another way to cut light is to use the fibreglass mesh screen like for door and window screens.

[Steven Pro]

Ok, I found my notes. This was brought up by Dana Riddle and Andy Amusen at MACNA XI in Louisville.

Using eggcrate to focus light under the bulbs can increase the total light intensity into the tank by 25%, but you will also experience an overall loss of about 20% mostly around the edges. Basically, the eggcrate and its taper focuses the available straight down so that you lose less light. So you gain light in the middle, but lose light around the perimeter.

The important point to remember is this was in reference to DIY pendants and canopies, not to laying a sheet of eggcrate on top of your aquarium for jumpers.

[Snarkys]

i have to say that it is a pain in the *** to take off and on everytime you need to get in the tank . i think i may try cutting it in half .

[Snarkys]

Originally posted by StevenPro
No, you want the narrow part towards the light. So that it looks like this when viewed from a cut away side,

|\ /\ /\ /\ /\ /\ /\|

This way it grabs the available light and focuses it downward. Dana Riddle talked about this at a MACNA several years ago. I believe it was the second Louisville conference.

http://www.thekrib.com/Lights/reflectors.html#24