Well, they vary depending on the plants light needs from 14" to 2 feet away. I had to use some shade cloth to provide for some species. Using both a red and a blue bulbs 50:50 does really well at getting plants to flower, much better than my cloudy windowsills.
Shade cloth for plants under flourescent bulbs.....that blows my mind! Are T5's also the regular 4' long tubes?
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DaveW
"Every time you spend money, you're casting a vote for the kind of world you want." ~Anna Lappe
Because the light level changes over time, T5 are the more stable out of all of the fluorescents I believe. But still what I like about them is their energy produced (to feed the plants) Vrs energy consumed (what you get charged for), as they are rather energy efficient.
Good explanation! I will still probably go this way, but want to cover my bases. Right now I'm thinking 3 or 4 of the 48" bulbs with a mix of daylight and warm (if possible).