humidifiers

does anyone add anything to their hummidifier water or should i just use 24 hr water ?

Manufactures recommend distilled water. I use ro in mine. DOesn't really matter that much. I figure they will last a year or two then it will be time to buy a new one. SO I won't have to clean it out once, not a big difference IMO. VV

and my humidifier runs when my lights are on or constantly ?

I run mine constantly. It sits by my heater, and the plants are on the other side of a curtain from both the heater and humidifier when the lights are off. My 'fresh air' system is on the plant side of the curtain. I have been able to keep it in a 20% range (Between 40 and 60rh) for the (24) hour period. Really depends on balance between air handling and temperatures. By having good air movement 'thru' the grow area you avoid the problem of having the rh too high when the lights go off. In addition to that I have a wall mounted oscillating fan and a fan at floor level that stay on 24/7.
I have several other fans that I can use, not necessary here in the winter. I have to spend the money on heat and humidity replacement and keep 'fresh air' available to the plants in order to utilize the space I have.
By the way, I may have just rambled on about nothing. My humidifier has 'Rh Level' controls, it only runs if the rh is below 50%.?? VV

so where should i have my hummidifier and fans placed ? i am growing in a closet and have my air intake at the bottom of the door and my exhaust at the top so a good ammount of air circulation.

so what hummidity level are u maintaing your room at 60-80 % ?