# Adding Tin Foil to a Canopy?



## tuffgong (Apr 13, 2010)

No, foil is not a good reflector of light. You can switch to mylar for slightly better reflective qualities or you can paint the inside of the canopy all white.


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## Nue (Dec 27, 2009)

Im not absolutely certain, but I think foil breaks up light in a bad way.


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## ar0wan (Oct 27, 2010)

There is no way it could make it worse than black plastic 
I've used foil lining my lights for years
I have no proof it does anything
GL


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## Wicket_lfe (Aug 21, 2008)

ive done the same as arowan. just added more foil to the inside of my light. Def better than black plastic. the after looked better than the before, so I don't see why not. Its better than nothing.

There is always one side of the foil that is shinier than the other though, so keep that in mind.


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## Hoppy (Dec 24, 2005)

I have tested aluminum foil vs white paint vs aluminized mylar, all with the same reflector shape and location, and with the same bulbs. I found that aluminum foil was the best of the three, a little better than white paint, and a lot better than the mylar. Because that was nothing like what I expected, I repeated the test with different lights, with the same results.

The reason I finally figured out is that reflectivity, the ability of a surface to redirect the light hitting it, isn't nearly the same as the ability of a surface to act as a good shaving mirror. Mylar is by far the best mirror, but you can easily discover that a lot of light goes right through the mylar. Really good white paint is a great reflector, even though the reflection is a diffuse reflection, so it doesn't work at all as a mirror. Aluminum has long been known to be the best reflector of all. Telescope mirrors are always aluminum plated, for example. Aluminum foil is thick enough that no measurable light goes through it, and almost all of the light is reflected. Crumpling the aluminum foil prevents it from acting as a good mirror, but the light is still being reflected, but is more nearly diffuse reflection.


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## zavikan (Jan 5, 2009)

*chrome tape*

title says it all. You can pick up a roll of chrome tape at an autopart store like "Advance" for $3. This stuff is like a MIRROR (who knows how scratch resistant). Insanely reflective. I just cut tape lengths to fit. its held up for a year so far, no issues.


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## chad320 (Mar 7, 2010)

zavikan said:


> title says it all. You can pick up a roll of chrome tape at an autopart store like "Advance" for $3. This stuff is like a MIRROR (who knows how scratch resistant). Insanely reflective. I just cut tape lengths to fit. its held up for a year so far, no issues.


Ive used this tape too.


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## tuffgong (Apr 13, 2010)

Hoppy said:


> I have tested aluminum foil vs white paint vs aluminized mylar, all with the same reflector shape and location, and with the same bulbs. I found that aluminum foil was the best of the three, a little better than white paint, and a lot better than the mylar. Because that was nothing like what I expected, I repeated the test with different lights, with the same results.
> 
> The reason I finally figured out is that reflectivity, the ability of a surface to redirect the light hitting it, isn't nearly the same as the ability of a surface to act as a good shaving mirror. Mylar is by far the best mirror, but you can easily discover that a lot of light goes right through the mylar. Really good white paint is a great reflector, even though the reflection is a diffuse reflection, so it doesn't work at all as a mirror. Aluminum has long been known to be the best reflector of all. Telescope mirrors are always aluminum plated, for example. Aluminum foil is thick enough that no measurable light goes through it, and almost all of the light is reflected. Crumpling the aluminum foil prevents it from acting as a good mirror, but the light is still being reflected, but is more nearly diffuse reflection.


I rescind my statement! Hoppy The God of Planted Tank Lighting has spoken. Thanks for sharing your results and experience!


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## Hoppy (Dec 24, 2005)

Once again, don't confuse mirrors and reflectors. Mirrors need to reflect an accurate image, so you can shave your chin without it being your nose, for example. But, reflectors are for redirecting as near 100% of the incident light as is possible, with no regard for how accurate the reflection is. A house painted with ultra white paint reflects sunlight so effectively it is painful to look at on a sunny day. That is because good ultra white paint reflects almost 100% of the light that hits it. And, that is what we want in our aquarium reflectors. (Fish don't shave!)


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## chad320 (Mar 7, 2010)

Hoppy said:


> Once again, don't confuse mirrors and reflectors. Mirrors need to reflect an accurate image, so you can shave your chin without it being your nose, for example. But, reflectors are for redirecting as near 100% of the incident light as is possible, with no regard for how accurate the reflection is. A house painted with ultra white paint reflects sunlight so effectively it is painful to look at on a sunny day. That is because good ultra white paint reflects almost 100% of the light that hits it. And, that is what we want in our aquarium reflectors. (Fish don't shave!)


I use Rustoleum gloss white oil based if that helps anyone. Brush first then lightly sand and spray.


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## Hawkian (Apr 14, 2010)

Thanks all! I like the chrome tape idea... thanks zavikan!

This is turning out to be a very frustrating endeavor for me. My tank canopy comes with 2 T8 fixtures with a max of 20W each. It's a 32G, which means I get an average of 1.25W/G in that tank... which is not enough to be able to keep plants healthy based on every forum I go to. It also seems that every manufacturer I look at has that problem: the light fixtures in the canopy do not accommodate for anything more than aesthetic lightning and ends up being dysfunctional for keeping plants. And every alternative i look at is super expensive. I don't know if the chrome tape can intensify the amount of light in the tank but it cannot hurt at this point...


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## Hawkian (Apr 14, 2010)

I am just now realizing that I never explained what I am trying to accomplish. 

Based on most of the reading I've done for keeping a planted tank, it seems that 2 to 5 watts per gallon is acceptable for keeping a planted tank. The plants I keep buying keep dying from the bottom up because of too little lighting but the options I have to adding light to that tank are very limited or very expensive.

I am now contemplating cutting out 2 holes on the top sides of the canopy I currently have so I can add some lighting through there but I am hesitating due to the positioning of the lights that would get added.

So I'm looking for creative alternatives that will not cost me an arm and a leg and allow me to keep plants, or get my light output within the 2 to 5 watts per gallon range...


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## Hoppy (Dec 24, 2005)

Hawkian said:


> Thanks all! I like the chrome tape idea... thanks zavikan!
> 
> This is turning out to be a very frustrating endeavor for me. My tank canopy comes with 2 T8 fixtures with a max of 20W each. It's a 32G, which means I get an average of 1.25W/G in that tank... which is not enough to be able to keep plants healthy based on every forum I go to. It also seems that every manufacturer I look at has that problem: the light fixtures in the canopy do not accommodate for anything more than aesthetic lightning and ends up being dysfunctional for keeping plants. And every alternative i look at is super expensive. I don't know if the chrome tape can intensify the amount of light in the tank but it cannot hurt at this point...


Is that a 30" x 12.5" x 20" tank? If so, you could do a cheap modification to the canopy/hood to put sockets for screw-in bulbs in it, then use 4 - 20-25 watt screw-in CFL fluorescent bulbs and get good lighting. If you also make a simple DIY aluminum sheet reflector, you can double the amount of light the bulbs give you.


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## Hawkian (Apr 14, 2010)

31" x 14" x 18" actually but close enough I think. Good suggestion... thx Hoppy!


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## forddna (Sep 12, 2007)

And how is this modification done? (T8 to screw in CFL sockets)

What's the best way to fasten the aluminum foil, guys?


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## ReefkprZ (Aug 21, 2010)

and my wife thinks I'm nuts when I buff the inside of the aluminum domes on my clamp lamps....


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## bsmith (Jan 8, 2007)

ReefkprZ said:


> and my wife thinks I'm nuts when I buff the inside of the aluminum domes on my clamp lamps....


I have done this with mothers chrome polish and it works great. 

OP, I know you are trying to save money but I know with some of my own DIY endeavors after completing the task to my liking I spent much or more money and had a lesser quality product than if I had just bought what I was needing all in one. 

Have you looked at any of the AH supply reflectors?


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## agimlin (Sep 25, 2010)

i put foil on my 10g hood with 2 zoomed 10w compact florescent bulbs with hot glue. it is kind of wrinkly but looks like more light is reflected which is funny because after i did that my java fern started to melt. if any one could explain that would be great. dont mean to highjack the thread


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