| I started out using full spectrum tubes - purchased at Home Depot - they seem to work well. I have since added more lights and have now also added growlux tubes and cool whites - no particular reason - without doing a scientific test I have not proved anything one way or other - so far everything I have used seems to work. Have done a lot of reading and I know that our plants like the blue end of the spectrum (which cool white provides - and these are the cheapest bulbs) and they also like the red end for blooming (which either full spectrum or growlux bulbs provide).
One thing I have definately determined, you cannot get your plants too close (except do not touch the tubes or it will burn for some reason). They will also not provide enough light to bloom medium or high light need plants - only the low light need groups like phals and paphs and similar. mike |