I took those pictures.
Under the bench are 50G barrels of water. The tent is a bit under 5'X4X31/2'. Heavy plastic stapled to back, top and sides, hanging loose in front, but can be secured. It's about 5 degrees warmer inside the tent than in the greenhouse, and steady, even though the heating pads haven't come on at all. The plants themselves give off enough heat. Once they grow bigger, I'll have to keep the flap open all day, or they'll start wilting.
The wire coming from that pot is for the soil thermometer.
The heating pads (very useful; not that expensive), their controller and light fixtures are plugged into a power bar, separate from the lights over the tanks, so I can keep them on longer.
Greens like it e cooler than the baby tomatoes and peppers. I've been trying all kinds of plants in the hydroponic tank - a squash seems to be doing well, but the cilantro didn't make it and the tomatoes had to be rescued and planted in soil. That was back in December. They're doing all right.
