I was just thinking... What's your lighting schedule like? Do you have to keep the lights on 24/7 to keep the temp up in that contraption, or does it hold heat for long enough to give the lights a break for a few hours?
Also, is there any kind of air circulation?
The lights are 16-8 but each level alternately is off, so this way there is alway heet from te light.
there is a fan on the second level top, forcing the air to go down on the first level.
The front door is open about 4" to let the heat go to the third floor.
And the third floor has a side that is open to let heat go out.
there is a 750 watts heater element under the fan, controled by a thermostat
it is used only when I start my seedling and I want to keep temp near 84 °F
but at his time the door are closed to keep heat inside