Suggestions concerning temperature

[Matty101]

Is 18-19 degrees celcius 75% humidity to cold and dry?...I'm running a 400w MH about 14 inches away from my seedlings..no tent..8 by 10 room built, wrapped with reflective white wall ..taking into consideration it's a colder day and temperature is going to rise daily until cooling will be needed should I be running hotter for the first stages of seedling life?

 

[Canuck147]

It's not too cold - just make sure your pots are off the floor - riser of some kind to raise them a bit( I use old bbq grates) so they won't be as cold but more of the ambient temperature of the room air.

 

[vostok]

Is 18-19 degrees celcius 75% humidity to cold and dry?...I'm running a 400w MH about 14 inches away from my seedlings..no tent..8 by 10 room built, wrapped with reflective white wall ..taking into consideration it's a colder day and temperature is going to rise daily until cooling will be needed should I be running hotter for the first stages of seedling life?

Not at all ...all the more reason to consider making seeds to aclimatize the plant for later generations
any lower then you are in the mold zone 12-16c
applying neem oil to prevent molds and bugs is good, as neem oil is systemic and organic

raising of the floor to the light I use dvd covers lolol (tax deductable too) ...lol

keep a fan close to ensure those stomata stays open

good luck