Aluminum foil is actually really good, as long as you avoid tearing it. That's why I switched to mylar....but mylar (at least mine) lets some light through. I can see the bulb throu the stuff, but it's kindof cool to examine it comfortably.
The most durable would probably be mirrors?
Crinkly, like foil, mylar etc... will "shred" the light into many very bright spots, and many dark spots. This is not good for even lighting on the leaves. It has been reported (rarely) to cause heat damage to leaves of cannabis.
Rough surfaces, like rolled on paint and the like...just absorb the light by reflecting it back upon itself before it "escapes" the surface texture. Which results in light loss.
By far the best a person can do, is to use a high titanium white FLAT spray paint. This will give the best reflectivity with the least amount of light loss during the process.
"the memories of a man in his old age, are the deeds of a man in his prime"
Yeah, it does let light through - but it's much like you can see through a one-way mirror... the reflective side is still highly reflective. The scratches - yeah, it does scratch pretty easily. Ya got me there.
I believe there is a thicker version at the place I linked to but it's correspondingly more expensive.
To answer the mylar question at walmart
No we do not sell rolls of mylar, but as someone pointed out we DO sell "emergency" blankets or "space blankets" as others call them, which is just a mylar sheet, in my sporting goods department, the company who makes them that we have, is called Ozark Trail.
i use mylar on my tank and have not had a problem with it. its just a pain to keep straight and wrinkle/scuff free... but if you can manage to keep from moving it around or having prying hands play with it, it is great stuff...
Mylar burning cannabis, sorry but these plants are certainly not cannabis, which i have experience with growing (legally of course, when i was a designated grower for a family member i shall not name for security reasons). And even then, I never had a problem with mylar causing leaf burn on them, if the plants are kept well hydrated and the light source at the right distance, there should be no reason for the mylar itself to cause any form of leaf burn to the plants... more likely the problem would be the heat from the lights, and how mylar (holding in more light) will keep it a wee bit warmer, drying out the plants faster than normal and boom, brown leaves...
I've seen both mylar and panda white, under different names of course. Mylar is better, but still didn't completely satisfy me. (I've actually reversed it and used the black side for some time. It's a cheap aquarium background, too.) I wonder if there's any kind of reflective material that would match a mirror?
Carnivorous plants paludarium:
I just ordered thick white foam boards at Walmart. I'm planning on covering one side with aluminum foil and when placed on the walls of the tank the foil would be facing in towards the plants.
"I may be on the side of angels, but do not mistake me for one."