For a skylight applicaton, IF you are near a wall, two 4' x 8' sheets for "opposite walls" of mirrored acrylic could be curved in a nearly parabolic curve, from 4' wide at the top, to whatever tank width that you desire, with flat sheets at the sides, to make your "collector-amplifier". If you are 4' square wiyh the skylight, for instance, and run this into a 48" x 18" tank, you have captured 16' sq. ft. of light.
A 10" Sola Tube only delivers .55 sq. ft. per tube, so even if the skylight method was only half as effecient as the Sola Tube, 4 Sola Tubes offer a total of 2.2 sq. ft. of area, whereas the skylight version, even when rated at 50% would effectively deliver 8 sq. ft. of sunlight.
This mirrored acrylic sheet is readily available in 1/8" thick sheets, and is not that expensive. I think the relative effeciency would actually be better than 50%. It would require a bit of "boxing" in the rafters, but it wouldn't be that bad.
I just happened to have some of this for a diy hood I've been designing, and the skylight questions here got me to thinking.
Just some food for thought, this is a great thread by the way. Thanks for all the pictures Jim, and the best of luck, with corraling "Murphy". :thumbsup:
> barryhc :beachbum: