The humidity in the enviroment is the amount of water vapor present in the air. Most growers know that humidity in excess of 85% percent increases the probability of the appearance of bud mold. The humidity is also critical during germanation when the seedlings are extremely fragile. Humidty should be kept over 80% at this stage in the plants life to prevent the soil from drying too fast.

Experimentation has shown that a relative humidity of 65% to 80% increases growth rate. Below this level the plants develop extremely narrow and tissue paper thin leaves to try to prevent excess loss of water. Above 80% relative humidity the plant have trouble disposing of toxic chemicals through evaporation

Now you know the basics. Learn how to grow cannabis like a pro!!!


source. Indoor Cannabis Cultivation

source. Grow Guide | CANNA UK
PUT THIS INFO IN
20L TANK
EC OF RO WATER 0.0
LIGHT FEEDING.

HUMIDITY

The humidity should be kept high (around 90%) unless over watering has occurred and the soil needs drying quickly. Cannabis doesn't like its roots to be wet all the time, so don't water every day unless the temperature is quite high. If proper ventilation is maintained, problems like fungus and algae should be minimal. Average watering solution usage: 10 days after transplant, 1 Quart (946 ml) 20 days after transplant, 1.5 Quarts (1419 ml) 30 days after transplant, 2 Quarts (1892 ml) During Flowering, 1.5 Quarts (1419 ml)

SOURCE. Advanced Cannabis Growing Guide


here you go mate..

sorry for my little rant earlier. i have alot on my mind at the moment.