aluminum tape reflector


Junior Poster
Dec 25, 2008
My lights are purely DIY stuff, as at a swap meet I bought 10 ARO as-220 vho ballasts cheap. Currently my reflectors consist of aluminum tape stuck to the top halp of my flourescent bulb tubes, blocking light from escaping to the top at all. Is there any value to this at all? Am I wasting my time? Anybody done any testing of this sort of set up? I assume decent reflectors could improve performance.


Prolific Poster
Dec 23, 2008
British Columbia Canada
To my understanding aluminum actually absorbs light even though it has a shiny surface. High polished aluminum is what you want but if you are using aluminum foil or tape its aparently not useful. White is a much better reflector although not the best and mirrored surfaces are also very good.
I suggest doing some looking around first to get ideas of other DIY reflector projects.


Lifetime Charter Member
Lifetime Member
Jan 24, 2005
Sacramento, CA
Remember, in a fluorescent tube it is the phosphors on the inner surface of the tube that are emitting the light. When you put even a good mirror surface on the outside of the tube you just reflect light back to the phosphor, not out the opposite side - the tube is virtually opaque, so light can't pass through it well at all.

The reflective surface needs to be on a surface away from the bulb, and that surface needs to be tilted so the light from the back side is reflected so it doesn't just bounce back at the tube. One way to do that is to use an inverted "W" shape reflective surface. The light then strikes one slanted surface, reflects to the other slanted surface and down into the tank. Here is a sketch of what I am referring to: (This isn't the only way to do this, but it is one easy way.)


Junior Poster
Nov 12, 2008
as vaughn says, it is counterproductive. you have less light and actually cause the bulb to run hotter. once when i needed a quick, dirty and cheap hood, i just taped aluminum foil to the inside of my cover making a really cheap reflector. remember that aluminum is a conductor and don't short circuit your wires with it. always use a GFCI on aquariums.