I just received the components for a misting system for my small gh. The "kit" comes with a timer to activate the high pressure pump BUT, I'm thinking of replacing the timer with a humidistat.

Seems obvious to me that the humidistat is better BUT...I'm also expecting the misting system to help keep temps down in summer.

If I use the timer, it seems to me I have the chance of over humidifying the gh or having it not provide sufficent water vapor to help cool, especially if the exhuast fan has been tripped on (from high gh heat) just before the misting system pump is activated by the timer.

Conversely, if I use the humidistat, it seems to me that once the exhuast fan comes on it will just suck out the water vapor from the system, reduce the possibility that the vapor will help cool, and run until the temp drops sufficently to shut off the fan.

It seems to me that the humidistat approach is better, humidity is kept high (reducing heat build up) before the temps reach exhuast fan levels but..hey I'm new to this.

GH has 60% cloth and receives reduced sunlight in late afternoon.

Thoughts or experiences ?