Al B Fuct Clone exhaust question?

Al B I am constructing a Clone box. It is just large enough for a dome with a heat mat under it. I have a two bulb standard T5 fixture in the top. It's one inch above the dome. (It's 24 inches wide by 12 inches deep by 18 inches talI) I am trying to duplicate the temps you have for your clones.I currently have a difficult time Cloning?What fan and what controller do you use to exhaust the heat? Or anyone else? Thanx

I just use a small exhaust fan with a thermostat set at 27 cel.

Dont need much attention for clones. Just water every couple days with fresh water and that's it. I keep my clones at 75-80degrees sometimes a little warmer with the heating mat and haven't lost a clone in quite some time now.

I found this on the net. Would it work with a computer fan? http://www.globalindustrial.com/p/hvac/fans/thermostats-controllers/mechanical-thermostat-fan-or-heater?utm_source=nextag&utm_medium=shp&utm_campaign=Thermostats-Controllers-nextag&utm_term=245823&infoParam.campaignId=WI