# Best reflector material?



## jaidexl (Sep 18, 2006)

I would use polished reflectors like the ones at ahsupply.


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## Shadowcat3 (May 12, 2009)

Oh sure, buy a REAL reflector!!!....Just kidding, I will check them out. Just wondering if there was a viable DIY option that was easy to do and cheap.


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## Hoppy (Dec 24, 2005)

The best reflective surface is what is used on big telescope mirrors - aluminum. The aluminum has to be very highly polished, like the "Miro 4" material that is now widely used for aquarium light reflectors.

When you talk about reflectors don't confuse that with mirrors. They are two entirely different things. A mirror is intended, in general, to reflect an image back to you that is very true to what is being reflected. You want to see accurate detail when you apply lipstick, right? But, you don't care if you are seeing that with only 20% of the light being reflected, which is why you can apply the lipstick using someones sunglasses as a mirror.

A reflector is best when 100% of the light that strikes it is reflected, and none is absorbed or transmitted through the reflector. If you want to reflect an accurate image of a very dim subject you also want the reflection to be accurate, which is why telescope mirrors use highly polished glass, for the accuracy, and a very uniform coating of aluminum, for the near 100% reflection. But, for our aquariums, we don't care if the reflection is acccurate or not. We just want all of the light from the bulb to be reflected towards the water.

White paint intuitively would not be a good reflector, but a freshly painted house, painted with pure white paint is a painful sight for the neighbors - it is so bright it hurts the eyes. That's why people don't buy pure white house paint - it is too good a reflector. There are some paints, usually called "ultra white" that are almost pure white, and they are as good an aquarium reflector as any other DIY material.

I tested ordinary white spray can paint vs aluminized mylar vs aluminum foil (somewhat crinkled), all on the same reflector, same bulb, with a PAR meter. The white paint and aluminum foil were both much better than the mylar. Because my white paint wasn't really really white, like ultra white paint, it was obvious that ultra white paint would have been better as a reflector than aluminum foil. Barium sulfate is an extremely good white pigment that can be added to ordinary white paint to make it super reflective. I was planning to experiment with some of that stuff, but gave it up when I couldn't get any cheap enough. It apparently is somewhat hazardous, so it isn't that easy to buy.


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## triple red (May 27, 2005)

white paint is good and cheap...
mylar is good if you can keep it from being wrinkled which will diffuse rather than reflect the light
mirrors will work but they are heavy
if you are ging to buy something....
tek reflectors are #1 for t-5... other wise you could use the ah supply reflectors


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## KC21386 (Feb 15, 2008)

I just use a sheet of thin, slightly polished, aluminum... I really dont feel that aquarium lighting needs to be nearly as precise as people make it out to be. 

I have three 26-watts spiral type compact fluorescent bulbs in a folded aluminum reflector hung by its own power cables has allowed me to grow anything I want in my 29gal tank.


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## Shadowcat3 (May 12, 2009)

Interesting and different opinions folks, thank you!! I guess it all works more or less and some are likely better than others, for reasons stated. Since I already have the mylar I guess I'll give it a a shot and try not to wrinkle it, granting that it may not be the ultimate reflector or the eqivalent of a nice German Miro4. You probably have a point KC. Sometimes getting that last 10% isn't really required to get the job done. I'm also an audiophile and people spend many kilobucks in search of equipment that they "think" sounds just a little bit better than what they bought last year or what the guy down the street has. At some point, unless you're quite wealthy, you just have to stop and be satisfied with the results...I don't think aquarists are that different and you can certainly spend a LOT of money in this hobby as well, if you just have to have the best, eh?!


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## Hoppy (Dec 24, 2005)

KC21386 said:


> I just use a sheet of thin, slightly polished, aluminum... I really dont feel that aquarium lighting needs to be nearly as precise as people make it out to be.
> 
> I have three 26-watts spiral type compact fluorescent bulbs in a folded aluminum reflector hung by its own power cables has allowed me to grow anything I want in my 29gal tank.


Please show us that lighting setup, either here or, better, in the DIY forum. It sounds very interesting.


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## Wasserpest (Jun 12, 2003)

I have found that mylar tends to get brittle over time, and after a while (year+) it starts to twinkle/twinkle down into the tank. Perhaps the material I used was inferior and this won't happen to you.

I have tried mirrors, and while they are cheap and reflect very well (I don't buy that lipstick stuff :tongue they are also heavy and somewhat difficult to position into optimum angles.

Don't underestimate white paint. It doesn't reflect nearly as well as polished aluminum, but it diffuses / spreads out the light which has its own merits for shallower, wide tanks. And, as mentioned, a quart of Ultra Pure White will go a long way if you don't wanna spend the dough to get the ultimate in reflectors.


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## GTR (May 27, 2009)

With store bought reflectors they've done some R & D to find the ultimate angles to reflect the light away from the bulb and not back at it. I think that's why if you're using just a flat surface under the bulbs you're better of with white since it diffuses it more.

If you're using multiple bulbs a setup with quality reflectors might not need as many bulbs and cost less long term.

I can hide the cost of reflectors but can't hide the electric bill every month. 
:wink:

SteveU


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## [email protected] (Jul 17, 2008)

THE best reflective material is a material from Dupont. It is 98% reflective while spectral aluminum is about 95% reflective. Ad in that this is not subject to spot oxidation and we have a nearly perfect material for aquatic installations. Now all I have to do it get it. 

I've been trying since March to get distribution or purchasing information but the Dupont rep in charge of the optical reflector program hasn't gotten back to me. <pause> I just called him an he says he forwarded my request to a Michigan rep in March, but I've not heard anything from them.


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## Hoppy (Dec 24, 2005)

[email protected] said:


> THE best reflective material is a material from Dupont. It is 98% reflective while spectral aluminum is about 95% reflective. Ad in that this is not subject to spot oxidation and we have a nearly perfect material for aquatic installations. Now all I have to do it get it.
> 
> I've been trying since March to get distribution or purchasing information but the Dupont rep in charge of the optical reflector program hasn't gotten back to me. <pause> I just called him an he says he forwarded my request to a Michigan rep in March, but I've not heard anything from them.


You should have mentioned that you can see a need for several hundred square feet eventually:biggrin:


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## Shadowcat3 (May 12, 2009)

The mirror thing sounded good to me, lipstick issues aside, but discarded it due to the weight, as mentioned. There is certainly merit to having a scientifically designed reflector to minimise restrike and improve focus or distribution. I'm going with what I have for the moment. If I don't like it I'll change it to something different later. I'm going to staple it to the top inside the hood, carefully, and see how it works out....probably pick up a bit of ultra white paint for the sides (insides).


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## [email protected] (Jul 17, 2008)

The distributor for THE best reflector material finally got in touch with me. 
I have samples coming. 

The only two drawbacks that I see currently are that nominal roll width is 58" and it will run a bit under $3.00 per square foot for adhesive backed material. Slitting for narrower bits adds cost. 
At least it can be rolled for shipping.


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## [email protected] (Jul 17, 2008)

*How did you know it was made for vampires?*



Hoppy said:


> You should have mentioned that you can see a need for several hundred square feet eventually:biggrin:


It reflects light better than a cheap mirror, but being white, guests won't notice that their host has no reflection.


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## Hoppy (Dec 24, 2005)

[email protected] said:


> It reflects light better than a cheap mirror, but being white, guests won't notice that their host has no reflection.


Be careful! Looking in a mirror has been the end of many a vampire:eek5: Test it carefully.

Do you have a weblink to that material? It sounds very good, even if I hope to never need a 58 inch wide piece of it.


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