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So I went out and gots me a large sheet (100cm * 70cm) of 4mm polycarbonate.
Its almost the size of the grow room and leaves a space of like 10 - 15 cm around the edges.
I'm hanging it up as a sort of shelf between the lights and the plants, dividing the room into two compartments.

It insulates very well, and shuts off a lot of heat in the upper compartment of the room.

Anyone think this is a viable alternative to a cooltube? Any opinions?
I'd love to hear any opinions, I'd hate to be ruining my light source one week into flowering...
I've researched like mad, and "visible light" appears to be the light spectrum that plants live in - it also shuts off UV light which plants generally don't like:

The characteristics of polycarbonate are quite like those of polymethyl methacrylate (PMMA; acrylic), but polycarbonate is stronger and more expensive. This polymer is highly transparent to visible light and has better light transmission characteristics than many kinds of glass. CR-39 is a specific polycarbonate material - although it is usually referred to as CR-39 plastic - with good optical and mechanical properties, frequently used for eyeglass lenses.
http://en.wikipedia.org/wiki/Polycarbonate
faithless Reviewed by faithless on . Sealing Off Heat With POLYCARBONATE Instead Of COOLTUBES . So I went out and gots me a large sheet (100cm * 70cm) of 4mm polycarbonate. Its almost the size of the grow room and leaves a space of like 10 - 15 cm around the edges. I'm hanging it up as a sort of shelf between the lights and the plants, dividing the room into two compartments. It insulates very well, and shuts off a lot of heat in the upper compartment of the room. Anyone think this is a viable alternative to a cooltube? Any opinions? I'd love to hear any opinions, I'd hate Rating: 5