Can a 1000w LED grow light be closer than 60cm (24") to a seedling?

Get a LUX meter from Amazon. This tool is very important. Seedling(s): 9-15k Veg: 15-25k Flower: 30-45k (I do 40k until the bud is fully formed than I do 45k) Try not to go over 55k LUX while in Flower, It could bleach your buds and also possibly give you foxtails especially with LED's.

"1000w" means a lot of different things.. sometimes it's "equivalent to 1000 watts" etc.. so more info needed on that. 20 dli is a good number to shoot for early on, but you need accurate specs and some general knowledge to guesstimate what your light is producing. fwiw, 100 ppfd is only 6.5 dli over 18 hours, which shows even the people repeating these suggestions don't know the math, lol. they are 50% off on lower value. in the end, you use the resulting growth to dictate how much to dim or how far away etc -- if it stretches too much, it needs more. If it is too tight between nodes, you reduce the light. while it doesn't apply to early on, later on the distance should be about best light distribution, then use dimmer or hours of operation to fine tune DLI.