Vadgoo, welcome to BYC If you go with the heat lamp make sure that directly under it is about the recommended temp for their age. The rest of their brooder area should be much cooler. For example for my two week olds under my light is about 90 degrees (checked with a thermometer) and the far...
At two weeks old they will still need some supplemental heat. Yours are close to the same age as mine. Two of mine have learned to fly to the top of my brooder also. I keep a wire mesh lid on my brooder to prevent escapes.
I built a small pen about 8 feet across in the yard and my week olds had their first "field trip". They weren't too thrilled to be out of the indoor brooder but ventured out of the safety of the cardboard box for a bit then retreated. I'm working on getting an outside brooder built out of an old...
Turn your heat lamp on a day or two early and get the temp stabilized. Lamp looks too low, put a thermometer under it and make sure it's ok They are too small to bake yet.
I think the roof of your cave is too high using a stool. Think about mama hen crouching down on the little ones. Probably just high enough for the chicks to walk under it would be closer. Maybe 3 inches. A Brinsea Ecoglow is what Blooie is copying.
I like the cave idea, I've heard of people hanging a feather duster so they can get under it also. Here's an old pic of my first flock. There are six in there. Towel wrapped candy box sitting on top of the heating pad. Took a while to warm up but it stayed warm for a while after turning it off.
My heating pad seems like medium is not warm enough and high gets really warm. Heat lamp seems easier to regulate by raising and lower it and gives a larger area of temperature variation. They can move a little farther away if they are too hot without getting completely away from the heat...
Here's my "Class of 2016". Just got them today. There is a heating pad wrapped in the T shirt, waiting on the heat lamp. Seems everyone was out today. One Buff Orpington, one each silver laced and golden laced Wyandotte and one Americana. City only allows 4 total
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