I'm in the same boat as you are--my dd has her 15 Cornish X fair chicks, now six days old and we seem to be constantly checking the temps. I bought a floodlight bulb that is a lower wattage (rather than a heatlamp), so that's on every evening, then anywhere between mid-morning and noonish she'll unplug the lamp and check the temp. When it seems to be getting higher she'll plus the fan in that I'd set up. It circulates the air above them--no direct blowing on them. They are in a 4'x4' (3' high) dog whelping box ...the door is two pieces of plywood that slide in a channel...I remove the top section so the bottom 14" piece of wood is there, the air blows in above them--hoping that will do the job, preventing too much hot, stuffy air. (we built a cover for the box, 2x4 frame with hardware cloth, so it's open too) So far, so good. Also, fresh water at least twice a day. I agree, I'd be hesitant about the pool for them right now--I've heard of misting them with water, but that's once their feathers come in, not when they are still mostly fluff.
I'd keep the air circulating but allow them an area where they can stay out of any drafts, if that makes sense, along with the fresh water, and be ready to adjust as needed. Good Luck!
Will look forward to hear what others have done/are doing to try to keep theirs safe.