I don't
know of any reason that the thick tubes are better than the thin ones,
though.

Our old mate "Logic" again. The thick ones have more surface area.
The thin ones DO get slightly warmer indicating wasted energy.

I've also tried comparing light from a 20W energy saver lamp and a 20W
flo' striplight using my cameras light meter and the strip wins hands down.

Surprisingly a daylight tube is better than Gro-Lux for plants.

That's my experience anyway.

Dave


------------------------------------------
The Hemyock, Devon, UK branch of The Residents Appreciation Society.

http://english.aljazeera.net