A question from a fellow grower:
I have a friend who has 4 t8 fluorescence on his plans right now which
are about 6 inches tall and 8 inches wide would it be okay to put a
thousand watt dual arc hps/metal halide on them now
Yes. You can place the plants under hits lamp.
On another note: I would wait a little bit longer. Perhaps transplant to next size pot, and allow roozone to establish.
If you place small plants under an intense lamp, such as a 1000 watt HID. You must keep it at a distance, and make sure that you do not melt the seedlings.
Make sure to always provide an adequate fan to send a slight breeze between the lamp, and the canopy of your plants. 
Hi Latewood, can i put my seeds under a 250 watt nova spectrum high pressure sodium lamp, or do i have to start off with the 36 watt cfl. I have a grow tent thats 60x60x140mm?. Yhanks.
david.
You should be able to put them under that light as long as it is not too close and you have temps under control. But why? You don’t need that much power for little seedlings.
You don’t even have to use a 36 watt cfl. A 15 watt, or a 45 watt might suit your purposes, it depends on the area and maybe how many seeds.
Seedlings and clones require about 400-1000 lumens per square foot.
Vegetative growth requires about a minimum of 2,000 to 3,000 lumens per square foot.
Flowering requires about 5,000 to 10,000 lumens per square foot, ideally, and can take possibly much more.
10,000 lumens is about the average power of the sun at sea level on a clear day at high noon. 8,000 - 12,000 lumens is supposed to be about the average power of the full sun without any overcast or no clouds depending on altitude and potentially other factors.
It’s not ideal, but you can make do with 2,000 lumens for an entire grow if necessary.