I've always brooded chicks using a securely hung heat lamp (2 lamps in bad weather in case a bulb blew) and a circular draft guard 6 ft in diameter, or in a black snake-proof home-made brooder with a wire mesh bottom and top. It was large enough so that my chicks (I'd brood as many as 25 at a time) had plenty of space and ventilation up to 4 weeks old. I kept them in it at least that long because a black snake can eat a bird the size of a full-grown quail. I often brooded them only at night when daytime temperatures were warm. If I used the circular draft guard method, I removed it once the chicks were older and started getting wing feathers, as I didn't want them to fly over it. By then they were old enough and large enough to find their way back to their food, water and heat. I always had good luck. I'd lose an occasional chick now and then, sometimes even at a later age. It is always upsetting and worrisome, but it happens. I also recommend starting with good stock, i.e., getting chicks from a NPIP-certified hatchery.