I put my seedlings under a 500w HPS and it works perfectly.
I think they'd grow beautifully under the 600, as long as you make sure the temp is fine and they aren't too close to the lights.

When the taproot comes out, I personally keep them out of the light until I see a sproutling. At the first site of the dirt being lifted, I put them under the light so photosynthesis can start asap.

Lowryders sound like fun.

<3
The Grim Reefer Reviewed by The Grim Reefer on . Seedlings under 600w HPS? Hey everyone, Ive managed to get hold of another 6 Lowryder seeds so Im in the process of germinating 4 of them (there were 10, my mate popped 3 and I popped 1 and they all turned out female, so Im hoping for some more females outta this lot). Anyway, would it be OK to put the seedlings under a 600w HPS, or should I stick the 25w flouro in there again? There would be a problem if I had to use the flouro, as I dont have anywhere to put the seedlings apart from with the more mature Low - Fiona - Rating: 5