First grow

it all depends on how you germinated them.. if you just put them into the medium and wait (what it seems to be) then it might take a week to 10 days.. some people prefer to put them into water or a wet papertowel on a warm surface a for initial germination, and once the taproot is out, place it into the preliminary medium (rockwool, jiffies, soil, whatever) as this will let you know sooner whether germination has been successful or not.. even then after burying it into the medium it might take a few days again until they eventually peek out of the medium. just give it some time and be patient.. 3 days isn't too much if they're buried :)

Nobody01's answer is pretty close to what I was going to say, but it all depends on what you want to do, if smell is not an issue, I prefer having the tent at positive pressure so everything blows out, helps keeps dust and debris down. If smell is a concern than you'd want negative pressure as Nobody was mentioning. Fan pushing into the tent = positive pressure, fan pulling out of the tent = negative pressure. If you are going to have an intake and an exhaust, make sure they are variable so you can adjust inflow/outflow to your liking. I run an intake and exhaust on variables and it gives me a lot of control over the temp/humidity if needed.

Hey Growmie, growing in tents can be tedious due to space. I personally just either take them out to water them or I use Plant Saucers, they go underneath the plant to catch the excess water. As far as airflow goes your can improve this with exhaust and intake fans or clip fans also. Hopefully, I answered your question and remember "Happy Growing" and "Free your mind one puff at a time"

Use both Switches! More light is not bad even if it's blue.