Hey medi thanks for the link,I can manipulate my R/H ,i have a humidifier and a dehumidifier,i can dial in R/H as needed,according to the chart my R/h should be between 70 and 80 percent.That seems a little high,and is this only in Veg.I usually use my dehumidifier the last two weeks of flower,to prevent mold .Is this an acceptable practice.We are very dry here in Tx.this time of year,our R/H runs about 50 to 60.Peace