If you need to gauge the lights but your hand under it if its too hot for your hand it’s too hot for plants. If not your good.
Why? I guess I don’t understand the reasoning.
Just a good way to tell if your light is too low.
just trying to find the right wattage and height for now.
One suggestion is a fan lightly blowing making seedlings tremble, it helps strengthen the stems alot
thanks for the tip. I still have domes (clear cups) on these.
perfect. domes are gone.
thank you for the input. greatly appreciated.
How long do you keep them on the mat?
I have to have mine on a mat because when I start my plants in April for an summer outdoor grow my basement is too cold. If you have warm enough temps you are A ok
I like to call them dancing ladies, just enough breeze to make them tremble 
a couple of them flopped right over. Had to do some re-potting. This was an indirect light breeze. Re-potted most of the lot. At this point I’ve spent a multitude of hours trying to figure out a decent light wattage and distance for the lights I am running for seedlings and coming up with no great answers. Learning a lot in the process but thats not helping me right now . I am beginning to think I should have just went with the smaller t5 lights from lowes or home depot for the seedlings.
those look great.
So sorry!! That is why I am not a fan sometimes of those domes, but other people can totally disagree with me. With that said maybe let them strengthen some, and if they get super leggy, when you go to repot them you can bury the stem some, but also you can run the risk of stem rot, but I have done it in the past with success. I feel horrible that a few toppled over. Many will say what I am about to say is wrong, nut here goes…I have a Kind LED K# Series 600watt light. When my seedlings pop, I flip that switch on that light. Below the light in my tent I strung up a light piece of fabric to break up the intensity of the light for 2 days or so, and then I take it down and have my light 36" over the seedlings, and I always have success. It came down to the fact that I didn’t want to buy yet another light, and add to my overhead as I had already spent $1200 setting up my tent. These are all my own opinions and it works for me, and I always have great growth and success. Seed genetics play a huge factor in how successful of a grow you will have in correlation with the stability of the seeds. I hope you aren’t upset with me for the fallen over seedlings. I just never do any of that stuff…I just premoisten my potting soil, put the soil in my solo cups, and pop a seed in, mist it some and put it in a warm dark place, and that is it. I planted 11 seeds this year, and 10 out of 11 germinated, a dud here and and there is too be expected. Of those 10 I kept 6 of them and gave 4 away to friends. All 10 are healthy, due in part to good care, but also great seed genetics.
I am here to help you the best that I can, and again, I am sorry about the seedlings falling over 
not your fault at all. I definitely am to blame. I appreciate all your input. I have moved both my topics to one spot if you want to check it out. Golgi apparatus thanks again.