Seedlings under 400W HPS?

Hi Guys,

What distance would you recommend having my seedlings under a 400W HPS? My 4 seedlings are 2 days old and the highest one is just under 4.5 cm hight with the inner serrated leaves still smaller than the 2 round ended. The lamp is 1.2 M above the seedlings with a temperature of 77oF at ground zero. I don't want the seedlings to stretch so does the current setup and hight sound OK, or should I replace the HPS with a CFL until the seedlings are more established and can handle the HPS at a lower height?

Baz

Use CFL's instead of the HPS for now. HPS light is far too intense for young seedlings, and you could risk burning them up.

The redder spectrum from the HPS can play a part in promoting male sexual expression. You want a light on the bluer end, such as a CFL, cool white flouro tube, of MH.

I get lost, as soon as the metrics start.